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International audience; Abstract Free-range livestock are exposed to environmental contaminants by ingesting contaminated matrices mainly soil. Several works evaluated precisely the soil ingestion and its variation factors in ruminants. Contrary to temperate grazing systems, tropical ones were poorly documented whereas weather or traditional grazing practices may change models established in temperate systems. The study was performed in the French West Indies, which are concerned by a widespread environmental chlordecone contamination. The work evaluated daily soil and grass ingestions by tethered growing bulls grazing on a very high sward close to 50 cm for 11 days without being moved. This grazing management is representative to local practices by small farmers or not professional holders and allows completing the results previously obtained. Daily soil ingestion did not significantly increase across time and was on average 26.9 g dry matter/100 kg body weight (i.e. 1.4% of the total mass ingested). Marked individual variations indicated that exposure risk assessments would require experimental designs based on a sufficient number of individuals. This study was also the first to investigate the changes in sward soiling with respect to the distance from the stake and reported lower soil loading on grass in the peripheral than central and intermediate areas.

The use of chlordecone (CLD), a chlorinated polycyclic pesticide used in the French West Indies banana fields between 1972 and 1993, resulted in a long-term pollution of agricultural areas. It has been observed that this persistent organic pollutant (POP) can transfer from contaminated soils to food chain. Indeed, CLD is considered almost fully absorbed after involuntary ingestion of contaminated soil by outdoor reared animals. The aim of this study was to model toxicokinetics (TKs) of CLD in growing pigs using both non-compartmental and nonlinear mixed-effects approaches (NLME). In this study, CLD dissolved in cremophor was intravenously administrated to 7 Creole growing pigs and 7 Large White growing pigs (1 mg kg−1 body weight). Blood samples were collected from time t = 0 to time t = 84 days. CLD concentrations in serum were measured by GCMS/MS. Data obtained were modeled using Monolix (2019R). Results demonstrated that a bicompartmental model best described CLD kinetics in serum. The influence of covariates (breed, initial weight and average daily gain) was simultaneously evaluated and showed that average daily gain is the main covariate explaining inter-individual TKs parameters variability. Body clearance was of 76.7 mL kg−1 d−1 and steady-state volume of distribution was of 6 L kg−1. This modeling approach constitutes the first application of NLME to study CLD TKs in farm animals and will be further used for rearing management practices in contaminated areas.

International audience; Chlordecone (kepone or CLD) was formerly used in French West Indies as an insecticide. Despite its formal ban in 1993, high levels of this pesticide are still found in soils. As such, sequestering matrices like biochars or activated carbons (ACs) may successfully decrease the bioavailability of halogenated compounds like CLD when added to contaminated soils. The present study intends (i) to produce contrasted sequestering matrices in order to (ii) assess their respective efficiency to reduce CLD environmental availability. Hence, the work was designed following two experimental steps. The first one consisted at producing different sequestering media (biochars and ACs) via pyrolysis and distinct activation processes, using two lignocellulosic precursors (raw biomass): oak wood (Quercus ilex) and coconut shell (Cocos nucifera). The chemical activation was carried out with phosphoric acid while physical activation was done with carbon dioxide and steam. In the second step, the CLD environmental availability was assessed either in an OECD artificial soil or in an Antillean contaminated nitisol (i.e., 2.1-1μg CLD per g of soil dry matter, DM), both amended with 5 wt% of biochar or 5 wt% of AC. These both steps aim to determine CLD environmental availability reduction efficiency of these media when added (i) to a standard soil material or (ii) to a soil representative of the Antillean CLD contamination context. Textural characteristics of the derived coconut and oak biochars and ACs were determined by nitrogen adsorption at 77 K. Mixed microporous and mesoporous textures consisting of high pore volume (ranging from 0.38 cm3.g−1 to 2.00 cm3.g−1) and specific (BET) surface areas from 299.9 m2.g−1 to 1285.1 m2.g−1 were obtained. Overall, soil amendment with biochars did not limit CLD environmental availability (environmental availability assay ISO/DIS 16751 Part B). When soil was amended with ACs, a significant reduction of the environmental availability in both artificial and natural soils was observed. AC soil amendment resulted in a reduced CLD transfer by at least 65% (P

A QuEChERS extraction method followed by HPLC-MS/MS analysis was developed to simultaneously analyze chlordecone and its metabolite chlordecol in animal livers. The overall method was validated with accuracy profiles according to the French Standard NF V03-110 and European Union guidelines. The validation was performed on bovine, ovine and porcine liver samples. Linearity, matrix effect, accuracy, within-laboratory repeatability, specificity, LOQ, Q/q relative ion intensities, and uncertainty were reported. Recoveries were between 70% and 120%. LOQs of 1.36 µg chlordecone kg-1 and 2.50 µg chlordecol kg-1 of fresh liver were found. Twelve contaminated livers of bovine, ovine and porcine origin from the French West Indies or samples from in vivo studies were analyzed. In these liver samples from contaminated animals, chlordecone was quantified at concentrations higher than the maximum residue limit and chlordecol in very low amounts in all the samples. In addition, these results confirm that chlordecone can be metabolized in ruminant species.

International audience; Sixteen weaned male Alpine kids (Capra hircus) were subjected to a 21-day oral daily exposure of 0.05 mg kg 1 BW. d 1 of chlordecone (CLD) and 0.30 mg kg 1 BW. d 1 of each non-dioxin-like polychlorinated biphenyls (NDL-PCBs, congeners 28, 52, 101, 138, 153 and 180). Four kids, identified as the CONTA group, were slaughtered at the end of the exposure, while the remaining animals (n ¼ 12) were fed with specific diets for an additional 21-day decontamination period before slaughtering. Kids from the DECONTA (n ¼ 4) group were fed a control diet, while those from the AC10% and PO8% group received pellets supplemented with 10% activated carbon (AC) and 8% paraffin oil (PO), respectively. CLD and NDL-PCB levels in blood, liver, peri-renal fat and muscles from different groups were analysed to compare the decontamination dynamics of the pollutants and to determine the efficiency of AC and PO to decrease the body levels of pollutants. After the decontamination period, the CLD levels considerably decreased (more than 60%) in blood, liver, muscles and fat. Concerning NDL-PCBs, the decontamination process was much lower. Overall, CLD appeared to be less retained in kids’ organism compared with NDL-PCBs, and the decontamination dynamics of these pollutants appeared to be different because of their specific physicochemical properties and lipophilicity. Furthermore, the dietary supplementation with AC or PO did not significantly affect the decontamination dynamics.

Chlordecone (CLD) is a Persistent Organic Pollutant used between 1972 until 1993 in the French West Indies (FWI). Due to its persistence and extensive application, a quarter of the total local agricultural acreage is still moderate to heavily polluted. In consequence, livestock may be contaminated at various levels. This is a major public health concern, particularly for local consumers. In order to better understand the fate of CLD in livestock organisms, in vivo studies are required. There is no information available about its metabolism and elimination in ruminants, common livestock in the FWI. To be able to monitor the fate of chlordecone and its metabolites in livestock and to assess if the compounds could be released in the environment, urinary and fecal samples were logically targeted. In order to reach this goal, robust and validated analytical methods are required. For this purpose, Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction methods were validated to analyze CLD and its metabolites in the urine and feces. The analysis was carried using liquid phase chromatography with tandem mass spectrometry and validated according to French standard NF V03-110 and SANTE guidelines. Matrix effect, Accuracy, within-laboratory repeatability, specificity, Q/q relative ion intensities and uncertainty were reported. Recoveries between 70% and 120% were obtained from urine and feces. The limits of quantification (LOQ) in urine samples were 0.1 μg CLD L−1, 0.1 μg total CLD (CLD and its conjugates)·L−1, 1.3 μg CLDOH L−1 and 2.4 μg total CLD (chlordecol and its conjugates) L−1 of urine. LOQ in fresh feces were 3.2 μg CLD kg−1 and 5.8 μg CLDOH kg−1. Contaminated urinary and fecal samples from ewes were analyzed to confirm the relevance of the methods. In urine, CLD and conjugated CLDOH could be quantified whereas only free CLD and free CLDOH were found in feces. These methods are essential for future toxicokinetic studies and also to estimate the environmental contamination.

The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils. CLD is known to be potentially transferred towards animal products of animals reared outdoors, mainly through accidental soil ingestion. Several studies indicate that soil bound CLD is bioavailable when administered to farm animals. Currently there is a need to quantify the level of CLD absorption and its toxicokinetic characteristics in the ruminant and particularly in the goat. These are considered as important farm species in the French West Indies. The objective of this study was to evaluate the absorption rate and the half-life of CLD in the non-lactating goat. The goats were administered either intravenously (i.v., n = 6) or orally (p.o., n = 6) one dose (1 mg kg −1 body weight) of CLD. Blood samples were collected at defined times up to 160 days post-dosing. CLD was analyzed in serum by high-resolution gas chromatography. A comparison of the area under the serum concentration-time curves (AUC) showed that the i.v. route is equivalent to the oral route. Thus, CLD is considered almost completely absorbed after p.o. administration, as shown by the mean absolute bioavailability. The comparison between the pharmacokinetic profiles of CLD following oral and intravenous dose showed a difference during the first 14 days and a similar kinetic after this period. The half-life of CLD in serum was close to 20 days. These results highlight a possible strategy of decontamination due to the short half-life of CLD, obtained in dry goats that did not excrete fat matter.

Soil is the main matrix which contributes to the transfer of environmental pollutants to animals and consequently into the food chain. In the French West Indies, chlordecone, a very persistent organochlorine pesticide, has been widely used on banana growing areas and this process has resulted in a long-term pollution of the corresponding soils. Domestic outside-reared herbivores are exposed to involuntary soil intake, and tethered grazing commonly used in West Indian systems can potentially favour their exposure to chlordecone. Thus, it appears necessary to quantify to what extent grazing conditions will influence soil intake. This experiment consisted of a cross-over design with two daily herbage allowance (DHA) grazed alternatively. Six young Creole bulls were distributed into two groups (G1 and G2) according to their BW. The animals were individually tethered and grazed on a restrictive (RES) or non-restrictive (NRES) levels of DHA during two successive 10-days periods. Each bull progressed on a new circular area every day. The two contrasting levels of DHA (P0.05) due to the lower DMI of RES compared with NRES treatment.

International audience

International audience; Children may be orally exposed to organic pollutants through involuntary soil ingestion. This study was aimed at determining the impact of the characteristics (organic carbon (OC), black carbon (BC), clay contents and pH) of ten contaminated soils on the bioavailability of non-dioxin-like polychlorobiphenyls (NDL-PCBs). Five juvenile male piglets were exposed to increasing amounts of each of the soils. These soil-fed groups were compared by a relative bioavailability approach (RBA) to a reference group fed with corn oil spiked with increasing doses of Aroclor 1254. After 10 days of oral exposure, the animals were sacrificed and NDL-PCB concentrations were determined by GC-MS in the adipose tissue. The relative bioavailability (RBA) factors were calculated for PCB 101, 138, 153 and 180. Despite high variations in the amount of black carbon (0.50 g kg(-1)-6.0 g kg(-1) d.w.) and organic matter (12 g kg(-1)-180 g kg(-1) d.w.), only 3 soils exhibited a significantly lower RBA for all NDL-PCBs, compared to the oil-group. High levels of OC (>100 g kg(-1)) and BC content (3.0 g kg(-1)) were related to a significant reduction in RBA. Overall, RBA was higher than 45% independently of the soil and the PCB congener.

National audience; The objective of this paper was to evaluate the transfer of inorganic and organic pollutants to livestock through ingestion of soil, plants, water or contaminated soil fauna, following spreading of residual-origin fertilizing materials (MAFOR) on grasslands. In the course of such an assessment the amounts of pollutants ingested, the fraction of pollutants to be extracted from the matrix and their fate in the body need to be considered. Field studies aiming at evaluating the pollutant transfer from MAFOR to livestock remain scarce. They are mainly based on sewage sludge application in grasslands and they do not allow estimating the impact of other forms of MAFOR. Taking into account the available knowledge on pollutants transfer to animal products, it appears that organic pollutants are more strongly absorbed and transferred than Trace Metals (TM). Mainly non metabolized pollutants significantly accumulate in animal products: organic pollutants generally concentrate in fatty tissues and products while TM are preferentially found in offal. However, a serious lack of knowledge about the behavior of emerging organic contaminants (brominated perfluorocarbons, phthalates, paraffin) or certain TM (vanadium, thallium) has to be noted. Overall, a significant transfer of organic and inorganic pollutants to animal products, following the application of residual-origin fertilizing materials on grasslands, cannot be excluded.; L’objectif de cet article est d’identifier les points de vigilance relatifs aux transferts de polluants inorganiques ou organiques vers les animaux d’élevage via l’ingestion de sol, de plantes, d’eau ou encore de pédofaune, consécutivement à l’épandage de MAtières Fertilisantes d’Origine Résiduaire (MAFOR) sur les prairies. Cette identification consiste à prendre en compte simultanément les quantités de polluants ingérées (quantité de matrice ingérée × concentration du polluant dans cette matrice), la fraction biodisponible et le devenir des polluants au sein de l’organisme. Les études réalisées en conditions de terrain et qui renseignent l’ensemble des données nécessaires pour estimer l’impact des MAFOR épandues sur prairies sont rares et peu conclusives. Elles reposent principalement sur l’application des boues de stations d’épuration sur des prairies et ne permettent pas de comparer l’impact des autres formes de MAFOR. Cependant, en prenant en compte l’ensemble des connaissances sur les transferts de polluants vers les produits animaux, il apparaît que les polluants organiques sont plus fortement absorbés que les Eléments Traces Métalliques (ETM). Seuls les composés peu biotransformés s’accumulent significativement dans les produits animaux. In fine, les polluants organiques se concentrent généralement dans les tissus et produits gras alors que les ETM se retrouvent préférentiellement dans les abats. Cependant, un manque manifeste de connaissances sur le devenir de contaminants organiques émergents (bromés, perfluorés, phtalates et paraffines) ou de certains ETM (vanadium et thallium) doit être signalé. De manière globale, les transferts de polluants organiques et inorganiques vers les produits animaux, suite à l’épandage de MAFOR sur les prairies, ne peuvent être exclus.

29th SEGH Conference on Environmental Geochemistry and Health, Toulouse, FRANCE, JUL 08-12, 2013; International audience; The pollution of soil with the pesticide chlordecone (CLD) is a problem for the use of agricultural surfaces even years after its use has been forbidden. Therefore, the exposure of free-ranged animals such as ruminants needs to be investigated in order to assess the risk of contamination of the food chain. Indeed, measured concentrations could be integrated in a lowered extent if the soil binding would reduce the bioavailability of the pesticide. This bioavailability of soil-bound CLD in a heavily polluted andosol has been investigated relatively of CLD given via spiked oil. Twenty-four weaned lambs were exposed to graded doses of 2, 4 or 6 mu g CLD/kg body weight during 15 days via the contaminated soil in comparison to spiked oil. The concentration of this pesticide has been determined in two target tissues: blood serum and kidney fat. The relative bioavailability (RBA) corresponds to the slope ratio between the test matrix-contaminated soil- in comparison to the reference matrix oil. The RBA of the soil-bound CLD was not found to significantly differ from the reference matrix oil in lambs meaning that the pesticide ingested by grazing ruminants would not be sequestered by soil binding. Therefore, CLD from soil gets bioavailable within the intestinal level and exposure to contaminated soil has to be integrated in risk assessments.

International audience; Humans are exposed to polycyclic aromatic hydrocarbons (PAHs), a family of ubiquitous neurotoxic pollutants, mainly through ingestion of contaminated food. Developing organisms can be exposed also to PAHs due to the ability of these compounds to pass through the placental barrier as well as through the breast milk. Previous animal studies have reported that the exposure of rats to a 16 PAH mixture at environmental doses strictly limited to gestation did not induce any long-lasting consequences, whereas gestational and lactational PAH exposure induced long-term behavioral and cerebral metabolic effects. In the present study, short-term effects of exposures to the same PAH mixture during gestation, or during gestation and lactation, were assessed by evaluating motor and sensory development of rat pups, and by measuring cerebral cytochrome oxidase activity (a marker of energetic metabolism) in different brain areas. Brain levels of PAHs and some monohydroxylated metabolites were also evaluated in pups at birth and at 21 days of postnatal life. No significant short-term modifications of behavioral development and of cerebral metabolism were observed following an early PAH exposure whatever the dose and the period of exposure. Surprisingly, the same brain levels of concentration of PAHs and metabolites were observed in control and exposed pups in both studies. These analytical results raise the difficulty in overcoming environmental contamination of control animals and the choice of such controls in experimental studies which focus on neurotoxicity of exposure to low levels of pollutants.

International audience; The exposure assessment of polychlorinated biphenyls (PCBs) contaminated soils is a critical issue in terms of human health, especially since little reliable information on transfer of PCBs to humans via involuntary soil ingestion is available. Indeed, young children with their hand-to-mouth activity may be exposed to contaminated soils. The current study addresses the impact of soil organic matter (OM) condensation on bioavailability of sequestrated NDL-PCBs. Three artificial soils (ASs) were prepared according to OECD guideline 207. One standard soil (SS), devoid of OM, and two amended versions of this SS with fulvic acid (FA) or activated carbon (AC) were prepared to obtain 1% organic mass. This study involved fourteen juvenile male swine as a digestive physiology model of young children. Animals were randomly distributed into 4 contaminated groups (3 replicates) and a control one (2 replicates). During 10 d, the piglets were fed AS or a corn oil spiked with 19200 ng of Aroclor 1254 per g of dry matter (6000 ng g(-1) of NDL-PCBs) to achieve an exposure dose of 1200 ng NDL-PCBs kg(-1) of body weight per day. After 10 d of oral exposure, NDL-PCBs in adipose tissue, liver and muscles were analyzed by GC-MS, after extraction and purification. Two distinct groups of treatments were found: on the one hand oil, SS and FA, on the other hand C and AC. This study highlights that condensed OM (AC) strongly reduces bioavailability whereas the less condensed one (FA) does not seem to have a significant effect. This result has to be considered as a first major step for further relative bioavailability studies involving mixture of different humic substances.

7th International PCB Workshop - Chemical mixtures in a complex world, Arcachon, FRANCE, MAY 27-31, 2012; International audience; Human activities are emitting persistent organic pollutants (POPs) to the environment. These compounds have raised concerns about the risk of transfer through the food chain via animal products. They are characterized by a strong persistence in environmental matrices and a lipophilicity which may lead to their accumulation in fat tissues. In EU Regulations (no. 1881/2006, 1259/2011), maximum acceptable levels for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and dioxin-like or nondioxin-like polychlorinated biphenyls (PCBs) in food of animal origin have been set. Transfer rates from contaminated fodder to milk have been established: for PCBs, the rate of transfer varies from 5 to 90 % and for PCDD/Fs from 1 to 40 %. The differential transfer of the compounds towards milk is related to the hydrophobicity of the pollutants and to their metabolic susceptibility. According to numerous authors, soil is the major reservoir for POPs, and its involuntary ingestion by farm animals reared outdoors may be the main cause of animal product contamination (meat, milk, or eggs). Recent studies seem to indicate that soil is a real risk matrix in terms of transfer of pollutants to the food chain. A POP crisis management is extremely difficult, since it impacts many farmers located in the contaminated area. The question arising is to know if livestock contaminated by POPs may be decontaminated and further used for their initial purpose. Recent data demonstrate that the decontamination process appear feasible and depends on initial level of contamination or the physiological status of the animals.

Quantitative health risk assessments are critical issues in management of contaminated soils and involuntary ingestion is one of the exposure pathway studied. Currently, as a margin of safety, 100% of the pollutants from the ingested soil is considered to reach the target organ and to exert toxic effects. However, it is established that only a fraction of the total ingested quantity really enters the bloodstream and reaches the target organs. In recent years, in vitro bioaccessibility tests aiming at estimating organic pollutant bioavailability and less expensive and easier to carry out than in vivo bioavailability tests, have been developed. Bioaccessibility is the fraction of an ingested compound that could be solubilized in the gastrointestinal tract before being absorbed. Few data are currently available concerning such approaches for organic pollutant contaminated soils. This study was carried out in order to compare bioaccessibility data with relative in vivo bioavailable ones in juvenile swine, a physically close model of young children. It concerned 8 "PCBs contaminated soils" which were collected at five different sites. Soil were freeze-dried and sieved to 500μm and homogenised.Characterization of soils were performed and were notably focused on organic matter (Black carbon amount, carbon organic content). This study involved five juvenile male swine per soil. During 10 days, the piglets were fed one of five doses chosen for one soil to achieve an exposure dose between of 200 and 3 600 ng NDL-PCBs.Kg-1 of BW per day in order to assess linearity of dose-response. This soil-fed group was compared to one fed increasing doses of spiked corn oil by Aroclor 1254. After 10 days of oral exposure, NDL-PCBs concentrations in adipose tissue, liver and muscles were determined by GC-MS, after extraction and purification. Linearity assessment were performed on NDL-PCBs levels in tissues using GLM procedure of SAS software. Bioaccessibility of each soil were assessed using the FOREhST procedure. Preliminary results highlight that condensed organic matter is a critical parameter affecting bioavailability or bioaccessibility of PCBs.

International audience; Livestock may be exposed to organic pollutants via ingestion of contaminated matrices such as fodder or soil. The question on contribution of soil-bound polychlorinated biphenyls (PCB) to livestock exposure was not yet considered. The aim of this study was to assess the relative bioavailability of soil-bound PCB by assessing milk excretion of indicator PCB (I-PCB) after ingestion by goats of graded levels of PCB (mainly PCB forms 153, 180, and 138) in soil-contaminated feeds or in oil-contaminated feeds. Eight multiparous Alpine goats were grouped in 4 pairs on the basis of body weight and milk yield. In each pair, one goat was assigned to the soil feeds and the other one to the oil feeds. The experiment consisted of a 7-d adaptation period, followed by a 96-d exposure period. The exposure period was divided into 3 successive 32-d periods during which each goat received either 3 soil feeds or 3 oil feeds, distributed in increasing rank of contamination. During the last week of each 32-d period, milk from each goat was collected during 3 successive 24-h periods, stored at -20 degrees C, and freeze dried before analysis (extraction by accelerated solvent extraction, followed by gas chromatography-mass spectrometry analysis). Bioavailability of I-PCB from soil or spiked oil feeds was estimated by means of the slope-ratio method from I-PCB concentration in milk in response to ingested I-PCB. Relative bioavailability was found to vary from 36 to 50% for PCB 118, 138, and 153 and it was 73% for PCB 180. When considered globally, the response obtained with the I-PCB was estimated to 51%. Relative bioavailability was not established for PCB 52 and 101, compounds known to be readily cleared and showing low concentrations in milk. For PCB 28, no significant interaction was found between matrix and dose. This experiment reveals that PCB bound to soil are potentially liberated from soil during the digestive process and may undergo absorption, distribution, metabolism, and excretion. Thus, soil has to be considered as a risk matrix for ruminants and rearing practices in contaminated areas should strictly reduce the risk of soil ingestion by the ruminants.

En France comme en Europe, de nombreux sites sont pollués par des PolyChloroBiphényles (PCB), majoritairement suite à l’abandon d’installations industrielles ou au recyclage mal maîtrisé de matériels contenant des PCB. La réaffectation de ces sols à de nouvelles activités nécessite la mise en oeuvre d’une évaluation quantitative des risques, permettant de valider la compatibilité entre le niveau de contamination et la maîtrise du risque pour les nouveaux usagers. Actuellement cette évaluation est conduite sur la base de la concentration totale en PCB dans les sols. Il s’avère que les polluants organiques peuvent être piégés par la matière organique des sols. La non prise en compte de cette réduction éventuelle de biodisponibilité peut conduire à une surévaluation du risque et à un surcoût économique significatif (Denys et al., 2009).Le projet a pour but de quantifier la capacité de différents sols à retenir les PCB et d’identifier les éventuels facteurs de variation. L’estimation de cette capacité de rétention est réalisée via l’évaluation de la biodisponibilité relative. Le modèle animal retenu est le porcelet dont le tube digestif est proche de celui de l’enfant.Les premiers résultats, obtenus sur sols artificiels, montrent que la qualité de la matière organique et particulièrement son degré de condensation est un facteur de variation majeur de la capacité de piégeage des PCB par le sol (Delannoy et al., 2013). Des sols prélevés sur une demi-douzaine de sites ont été caractérisés (teneurs en carbone organique, black carbon et PCB) et vont être testés à la fois en termes de biodisponibilité relative (in vivo) et de bioaccessibilité (in vitro) via le test Foresht, mis au point par le groupe BARGE.

International audience; The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils and of food chains. CLD may be transferred into eggs of hens reared outdoors, through polluted soil ingestion. Tropical volcanic soils display variable capacities of pollutant retention: CLD is less available and more persistent in andosol than in nitisol. The impact of soil type on CLD bioavailability to hens was tested through a relative bioavailability study. The deposition of CLD in egg yolk and in abdominal fat was measured in 42 individually housed laying hens fed with diets containing graded levels of CLD from polluted andosol, nitisol, or spiked oil during 23 days. Within each ingested matrix, the concentration of CLD in yolk and in abdominal fat linearly increased with the amount of ingested CLD (P < 0.001). However, the response to andosol diets and to nitisol diets was not different from the response to oil diets (P > 0.1), indicating that CLD was equally bioavailable to laying hens, irrespective of the matrix. This suggests that the hen's gastrointestinal tract efficiently extracts CLD from the two tropical volcanic soils, regardless of their retention capacity. Thus, hens reared on polluted soils with CLD may lay contaminated eggs.

Risk assessment of Polychlorobiphenyls (PCB) contaminated soils is a critical point in sanitary management all the more that few reliable information on transfer of PCBs to humans via involuntary soil ingestion is available. Indeed, young children with their hand-to-mouth activity may be concerned by an exposure to contaminated soils. In order to assess the possible impact of soil Organic Matter (OM) condensation onto bioavailability of NDL-PCBs a study completed in two parts was designed. The first study investigated the dose-response relationships in selected tissues. The second study t was subsequently completed to evaluate the incidence of organic matter condensation on NDL-PCBs levels in target tissues. In the first study, eight male piglets were orally exposed during 10 days to one of the four levels (190, 560, 940 and 1 310 ng NDL-PCBs.Kg-1 of Body Weight (BW) per day) of a corn oil spiked by Aroclor 1254. NDL-PCBs concentrations in adipose tissue, in liver and in muscles were determined for each congener by GC-MS after extraction and purification. Except for PCB 28, the analyzed levels were above the LOQs. A regression analysis showed a significant linear relationship between the administrated doses and the levels measured in the various adipose tissue, liver and muscle (R²>0.70) in a range of dose of 190 ng to 1310 ng NDL-PCBs. Kg-1 of BW.In the second study, three Artificial Soils (AS) were prepared according to OECD guideline 207,. One Standard Soil (SS), containing no organic matter, and two amended versions of this SS with Fulvic Acid (FA) or Activated Carbon (AC) were prepared to obtain 1% mass of organic. This study involved fourteen young male swine randomly distributed into 4 contaminated groups (3 replicates) and a control one (2 replicates). During 10 days, the piglets were fed AS or a corn oil spiked with 19 200 ng of Aroclor 1254 per g of dry matter (6 000 µg/g of NDL-PCBs) to achieve an exposure dose of 1.2 µg NDL-PCBs.Kg-1 of BW. Variance analyses were performed onto resulting levels of NDL-PCBs into tissues as repeated measures using MIXED procedure of SAS software. Significant treatment effect and two distinct groups of treatments were found: on one hand oil, SS and FA, on the other hand control and AC. This study highlights that condensed OM (AC) strongly reduces bioavailability whereas less condensed part (FA) doesn’t seem to have a significant effect.

Children are known to be a sensitive population which is potentially exposed to polychlorobiphenyls (PCBs) through soil ingestion because of their hand-to-mouth activity. Therefore, it appears essential to characterize oral bioavailability of PCBs and to assess the PCBs dose-response relationships. Young swine model was designed to determine the relative oral bioavailability of contaminants to young children and is a useful tool in health risk assessment. The present study investigated the oral bioavailability of indicator PCB (I-PCBs) in piglets and their dose-response relationships into selected tissues. Eight young swine male, individually housed, were orally exposed one of the four experimental mixtures (2 replicates) during 10 days. The four experimental mixtures were contaminated by graded levels of a corn oil spiked by Aroclor 1254 to achieve 190, 560, 940 and 1 310 ng I-PCB.Kg-1 of Body Weight (BW) per day. I-PCBs concentration in adipose and cerebral tissues, liver and muscle were determined for each congener. I-PCBs were extracted by Accelerated Solvent Extraction, analyzed by GC-MS and Limits of Quantification (LOQs) were estimated. For PCB28 and PCB52 congeners, levels measured in different tissues were below the LOQs. Regression analysis for other congeners demonstrated significant linear relationships between the administrated doses and the levels measured in adipose tissue (R²>0.70), liver (R²>0.77) and muscle (R²>0.77). The highest levels of I-PCBs and regressions coefficients were found in the liver tissue. Cerebral samples exhibited a nonlinear relationship; however this result needs to be confirmed by further experiments. The dose-response relationship in a range of dose of 190 ng to 1310 ng of Aroclor 1254 I-PCB per Kg of BW appeared to be linear in all studied tissues except the cerebral one. This result has to be considered as a first step for further relative bioavailability studies involving complex matrices like food, soil or dust.

International audience; The relative bioavailability of arsenic, antimony, cadmium, and lead for the ingestion pathway was measured in 16 soils contaminated by either smelting or mining activities using a juvenile swine model. The soils contained 18 to 25 000 mg kg(-1) As, 18 to 60 000 mg kg(-1) Sb, 20 to 184 mg kg(-1) Cd, and 1460 to 40 214 mg kg(-1) Pb. The bioavailability in the soils was measured in kidney, liver, bone, and urine relative to soluble salts of the four elements. The variety of soil types, the total concentrations of the elements, and the range of bioavailabilities found were considered to be suitable for calibrating the in vitro Unified BARGE bioaccessibility method. The bioaccessibility test has been developed by the BioAccessibility Research Group of Europe (BARGE) and is known as the Unified BARGE Method (UBM). The study looked at four end points from the in vivo measurements and two compartments in the in vitro study ("stomach" and "stomach and intestine"). Using benchmark criteria for assessing the "fitness for purpose" of the UBM bioaccessibility data to act as an analogue for bioavailability in risk assessment, the study shows that the UBM met criteria on repeatability (median relative standard deviation value 0.6) for As, Cd, and Pb. The data suggest a small bias in the UBM relative bioaccessibility of As and Pb compared to the relative bioavailability measurements of 3% and 5% respectively. Sb did not meet the criteria due to the small range of bioaccessibility values found in the samples.

International audience; Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous pollutants originated from incomplete combustion processes. Ingestion of contaminated food is the main route of exposure for humans. These molecules are able to cross the placental barrier and are also found in breast milk. Since PAHs are neurotoxic agents, the potential adverse effects of a perinatal exposure of the developing brain is a key issue for public health especially concerning PAH mixture. In this study, female rats were exposed trough diet to a mixture of 16 PAHs, at doses of 2 mu g/kg/day or 200 mu g/kg/day during gestation and 1.5 mu g/kg/day or 150 mu g/kg/day during breast-feeding period. To assess late neurotoxic effects in male offsprings, behavioural and cognitive tests were carried out and histochemical analyses using cytochrome oxidase as a cerebral metabolism marker were performed on adult animals. Results showed that anxiety-related behaviours significantly increased in exposed animals, but there was no significant alteration of motor activity and learning and memory abilities. Several brain areas of the limbic system showed a neuronal hypometabolism in exposed animals. This work highlights that exposure to PAHs at early stages of brain development can cause later troubles on behaviour and that PAHs are able to partly alter the central nervous system metabolism on adulthood.

International audience; Polybrominated diphenyl ethers (PBDEs) are flame retardants. Because of their high lipophilicity and persistence, PBDEs bioaccumulate in all abiotic and biological matrices. The aim of this study was to investigate the long-term neurobehavioral and physiological effects of exposure to environmental doses of PBDE-99 in adult rats. Rats received a daily administration of PBDE-99 for 90 days by oral gavage at 0.15, 1.5 and 15 mu g/kg, doses which are relevant of human exposure. Before and after the 90 days of exposure, behavioral tests including the open-field and the elevated plus-maze tests for locomotor activity and anxiety, and the Morris water maze for spatial learning were conducted. Physiological measures such as body weight, food and water consumption, organs weight, hepatic enzymes levels and PBDE-99 concentration in adipose tissue were also evaluated at the end of exposure. There was no effect on body weight, food and water consumption, organs weight, hepatic enzymes levels despite rising PBDE-99 concentration in adipose tissue with the doses tested. Moreover, there was no effect on locomotor activity and exploration, and spatial learning. Deleterious effects of PBDE-99 at high doses have often been highlighted in many studies after an acute dose whereas exposure during 90 days at realistic doses would have no significant effect in adult rats. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

International audience; Presently, few biomarker-based approaches are available for the evaluation of environmental exposure to persistent organic pollutants in dairy ruminants. In this study, goats (Capra hircus) were orally administered a mixture of pyrene, phenanthrene, and benzo[a]pyrene daily over a 40-d period (1 or 50 mg/d). Milk and urine 1-hydroxypyrene levels, ethoxyresorufin-O-deethylase (EROD) activity in peripheral blood lymphocytes (PBL) as well as urinary levels of 2- and 3-hydroxyphenanthrene were determined at 10-d intervals. 1-Hydroxypyrene excretion in milk and urine significantly increased and then achieved a plateau at 10 d. Transfer rates of 1-hydroxypyrene were calculated to be approximately 0.5 and 25% in milk and urine, respectively. Concentrations in milk and urine were proportional to the ingested doses. These results demonstrate that 1-hydroxypyrene in milk or urine may be used as a biomarker for evaluating the exposure of dairy ruminants to polycyclic aromatic hydrocarbons (PAHs) over an extended exposure period. Constitutive EROD activity in lymphocytes was 0.5 +/- 0.3 pmol resorufin/min/mg protein, and was significantly induced over the entire exposure time, before stabilizing after 40d at 6.30 +/- 1.3 and 18.89 +/- 1.12 pmol resorufin/min/mg protein for 1 mg/d and 50 mg/d doses, respectively. Induction kinetics were calculated using a logistic-like model and approximate dose-response curves were designed. We therefore propose EROD activity in PBL as a relevant, convenient, and noninvasive biomarker of subchronic exposure of dairy ruminants to CYP450 inducing PAH. Environ. Toxicol. Chem. 2011;30:1346-1353. (C) 2011 SETAC

International audience; Despite its interest, little is known about the potential of 1-hydroxypyrene to be used as biomarker of exposure of dairy ruminants (goat, sheep and cow) to pyrene or other polycyclic aromatic hydrocarbons (PAHs) and, to date, no clear approach has been proposed to evaluate and use this biomarking potential for evaluating exposure to pyrene and other polycyclic aromatic hydrocarbons also prone to contaminate the vegetal cover ingested by these dairy ruminants. In the present study, three Alpin goats were daily submitted to two different levels (0.04 and 0.28mg/day) of pyrene oral ingestion, together with phenanthrene and benzo(a)pyrene, during 1 week each. Extraction and HPLC-fluorimetry analysis results on 1-hydroxypyrene in milk and urine as well as on 1, 2, 3 and 4-OH-phenanthrene and 3-OH benzo(a)pyrene in urine were fruitfully combined with few recently published results on 1-hydroxypyrene excretion achieved in a former and similar experiment performed on a set of four goats with doses 1, 7 and 49mg/day/goat. Statistical analysis demonstrated the biomarking potential of 1-hydroxypyrene to be used for evaluation of oral exposure to pyrene under low and large levels of exposure and transfer (linear) equations were proposed. Finally, a literature based approach, combined with the achieved experimental transfer rates, was proposed for evaluating the amounts of 12 additional polycyclic aromatic hydrocarbons into the fodder, thus extending the potential of 1-hydroxypyrene in urine and/or milk to be used as a biomarker of oral exposure to PAHs. Keeping in mind that milk is much easier to sample as compared to urine, such approach may be used as a first step for evaluation of oral exposure of goat and likely other dairy ruminants to polycyclic aromatic hydrocarbons prior to any exhaustive, time and cost consuming analytical investigation.

International audience; Airborne polycyclic aromatic hydrocarbons (PAHs) are deposited on agricultural grasses. In turn, PAHs enter the food chain through animals eating grasses. However, the risk of food contamination, e.g. of milk, is unknown because mechanisms ruling the fate of PAHs during digestion by cows are not understood, especially in the rumen. Here, we studied the disappearance rate of phenanthrene, pyrene and benzo[a]pyrene, n-alkanes, and dry matter from contaminated grass samples in the rumen, the first compartment of the ruminant digestive tract. Three cows fitted with a rumen cannula were used for this study and the grass samples were incubated in sacco for 1, 3, 6, 12, 24 and 48 h. The results show that the disappearance rate of PAHs was fast and higher than that of n-alkanes. On average, 83% of PAHs disappeared after 1 h of incubation. Phenanthrene showed a disappearance rate higher than 90%. The findings suggest a fast desorption of PAHs from the surface of the grass leaves. The digestive hydrolysis of the grass is not required to release PAHs, contrary to other fractions. As a consequence, the bioavailability of PAHs is not limited by the grass.

The harmful effects of exposure to benzo[alpha]pyrene (B[alpha]P), which is a neurotoxic pollutant, on mammalian neurodevelopment and/or behaviour as yet remain widely unclear. In the present investigation, we evaluated the impact of the lactational exposure to B[alpha]P on postnatal development of pups and behaviour of young mice. The neurobiological effects of B[alpha]P during lactation were also evaluated on pups' brain. Here, we found that lactational exposure to B[alpha]P at 2 and 20mg/kg affects the neuromaturation of pups by significantly decreasing their reflex as highlighted in surface righting reflex and negative geotaxis tests. However, we noted a significant increase in muscular strength of lactationally B[alpha]P mg/kg-exposed pups, which was probably due to the impact of the exposure to this toxic compound on body weight gain. At the pup stage, lactational exposure to B[alpha]P also provoked a neurobiological change, which was assessed by determination of neuronal receptor gene expression. Indeed, a significant reduction in gene expression of 5HT(1A) receptors in pups exposed to B[alpha]P through lactation was found in comparison to controls. Additionally, attenuation in the expression of MOR(1) mRNA was observed, but statistically significant only in animals receiving the higher dose. Neither the expression levels of ADRA(1D) nor GABA(A) mRNA were altered. Interestingly, the harmful effects of lactational exposure to B[alpha]P on behaviour and cognitive function were still found despite a long post-weaning period. Young mice whose mothers were exposed to B[alpha]P displayed a disinhibition behaviour towards the aversive spaces of the elevated plus maze. Furthermore, a significant increase of spontaneous alternation in the Y-maze was observed, but only in young mice whose mothers were orally exposed to the lower dose of B[alpha]P. Our results suggest a close link between the neurobiological change highlighted in pups' brain and the different behavioural disturbances observed during postnatal development period until young adult stage.

International audience; This study aimed at determining the relative bioavailability (RB) of three soil-bound PAH model compounds (phenanthrene [PHE], pyrene [PYR] and benzo[a]pyrene [BaP]) in four lactating goats. RB was estimated by comparing the urinary or milk excretion of the major mono-hydroxylated metabolites of PAHs after ingestion of PAH spiked-soil and -oil feeds. A series of three increasing doses were orally administered in order to estimate the dose response of the two different matrices. The results of this study reveal that urinary excretion prevailed compared to milk excretion (30-fold higher). The recovery rate of mono-hydroxylated metabolites of PAHs in urine and milk indicate that PYR was absorbed at a minimum level of 36%. 3-OH PHE excreted in urine suggests a minimal absorption of at least 5% for PHE. 3-OH BaP remained under the limits of detection and quantification and no RB could be calculated for this compound. RB of soil-bound PYR compared to PYR in oil was 61% and 50% in milk and urine, respectively. Thus, a significantly reduced RB of PYR in soil has been shown. On the other hand, no significant differences were observed between oil and soil for urinary 3-OH PHE (RB = 100%). These results show that the soil matrix significantly reduces the bioavailability of certain PAHs. The decrease of bioavailability seems to be dependent on the compounds, i.e. higher for PYR than for PHE. This study also suggests that soil ingestion should be taken into account in risk assessment studies.

International audience; This experiment was aimed at determining the bioavailability of three polycyclic aromatic hydrocarbons (PAHs) in goats: phenanthrene, pyrene, and benzo[a]pyrene. A Latin square design procedure was carried out involving three alpine lactating goats and three PAH-contaminated matrices (soil, hay, and oil as a control). Milk and urine samples were collected to assess PAH and hydroxy-PAH excretion kinetics and to compare the carry-over rates for the different matrices. PAHs were found to be excreted mainly in urine; metabolite concentrations were about 20 times higher in urine than in milk. 1-Hydroxypyrene was the major metabolite in both body fluids (8000 ng/mL urine and 450 ng/mL milk); it may be considered as a valuable indicator of the ruminant exposure to PAHs. Apparent absorption of PAHs estimated by the metabolite excretion in urine and milk reached 34% for pyrene from soil, and the bioavailability of soil-bound PAHs was found to be similar to the bioavailability of PAHs from the other matrices.

International audience; Growth hormones (GH, somatotropins ST) exhibit numerous biological effects associated with growth functions. Recombinant GH (rGH) are produced in large quantities and widely used outside Europe to stimulate milk production and as a general growth promoter in meat producing animals. The use of this molecule in animal production is strictly regulated by food safety directives in force. The control of its potential misuse constitutes an analytical challenge which many laboratories have attempted to tackle over the last 15 years. Two strategies can be considered to demonstrate somatotropin treatment to animals, based either on direct or indirect methodologies. Direct methods are focused on the analysis of somatotropin itself, while indirect methods are based on the detection of biological biomarkers with concentrations dependant on ST. Recently, the detection of antibodies produced by the animal after treatment has shown promising results for screening the abuse. In the same time, the challenge of rGH monitoring in biological matrices by means of mass spectrometry has been overcome thanks to the development of efficient purification procedure combined with the use of last MS generation instruments. This presentation overviews the different strategies for the control of GH misuse, focusing on the more recent and promising ones.

International audience; Human activities produce polluting compounds such as persistent organic pollutants (POPs), which may interact with agriculture. These molecules have raised concern about the risk of transfer through the food chain via the animal product. POPs are characterised by a strong persistence in the environment, a high volatility and a lipophilicity, which lead to their accumulation in fat tissues. These compounds are listed in international conventions to organise the information about their potential toxicity for humans and the environment. The aim of this paper is to synthesise current information on dairy ruminant exposure to POPs and the risk of their transfer to milk. Three major groups of POPs have been considered: the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), the polychlorobiphenyls (PCBs) and the polycyclic aromatic hydrocarbons (PAHs). The results show that contamination of fodder and soil by these compounds is observed when they are exposed to emission sources (steelworks, cementworks, waste incinerators or motorways) compared with remote areas. In general, soil contamination is considered higher than plant contamination. Highest concentrations of POPs in soil may be close to 1000 ng/kg dry matter (DM) for PCDD/Fs, to 10 000 mg/kg DM for PAHs and 100 micro g/kg DM for PCBs. The contamination of milk by POPs depends on environmental factors, factors related to the rearing system (fodder and potentially contaminated soil, stage of lactation, medical state of the herd) and of the characteristics of the contaminants. Transfer rates to milk have been established: for PCBs the rate of transfer varies from 5% to 90%, for PCDD/Fs from 1% to 40% and for PAHs from 0.5% to 8%. The differential transfer of the compounds towards milk is related to the hydrophobicity of the pollutants as well as to the metabolic susceptibility of the compounds.

International audience; Single oral ingestion of phenanthrene was administered in lactating goats with the aim of characterizing its behavior and its biotransformation in milk and other excretion products. Detection and identification of the analytes (phenanthrene, 1-, 2-, 3-, 4-, 9-hydroxyphenanthrene and 9,10-dihydroxyphenanthrene) were achieved using GC-MS procedure. The blood kinetics revealed the presence of phenanthrene and its hydroxylated forms quite soon (3-7 h) after the oral administration. The high concentration of metabolites in blood (3-300 ng/mL) suggests a very fast biotransformation process of phenanthrene. A direct link between the lipophily and the presence of the molecule in milk or urine was established. Indeed, 94% and 99.6% of the excreted phenanthrene were recovered under metabolite forms in milk and urine respectively. The non-metabolized phenanthrene was principally found in faeces. The more the solubility increased, the more the compound was transferred through milk and urine; as a consequence, the 9,10-diOHphenanthrene appeared mainly in urine whereas phenanthrene was practically not detectable. These results provide original information on the ability of the dairy ruminant to metabolize and to transfer phenanthrene. The extremely low rate transfer of phenanthrene and its metabolites to the milk (0.25%) should not, therefore, be considered as a major health concern.

International audience; The increase in deposition of air pollutants such as the platinum group elements (PGEs) Pt, Pd and Rh, and polycyclic aromatic hydrocarbons (PAHs) from vehicles on plants has raised concerns about the risk for the quality of food and, in turn, for human health. Here, we report the first pollution maps of PGEs and PAHs at the agricultural scale. PGEs have recently emerged in ecosystems due to their massive use as catalysts in the automobile industry. PAHs are combustion by-products known for their carcinogenic properties. PAHs and PGEs emitted by vehicles can enter the food chain through deposition on plants growing near roads. Despite many investigations of PAHs and PGEs, knowledge on their spatial distribution near roads is very scarce. Here, we assessed their localization on the scale of an agricultural field close to a road with 7200 vehicles per day. While classical studies usually involve direct measurements of plants growing in the field, we used an alternative experimental approach to allow an unambiguous assessment of the pollution impact. Ryegrass (Lolium perenne) was first cultivated in pots in a closed greenhouse to isolate the plants from the outdoor atmosphere. Then, ryegrass pots were transferred to the agricultural field. The spatial distribution of PGEs and PAHs was assessed by placing ryegrass pots 0 m, 10 m, 25 m and 50 m from the road. This method thus allowed the measurement of PGE and PAH deposit from vehicle emissions during a known timeframe. After a one-month exposure, the PGE and PAH concentrations in ryegrass samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) and high-pressure liquid chromatography (HPLC), respectively. Our results demonstrate a significant effect of pollution by the outdoor atmosphere for Pd and PAHs. Indeed, the concentrations increased by a factor of 1.5 for Pd and by a factor of 7 for PAHs after one month's exposure in the isolated pasture. The results also demonstrate clearly the impact of road traffic. Indeed, the highest PGE and PAH concentrations were detected in ryegrass exposed at the road site. Pd and PAH concentrations decreased significantly up to 39% and 60%, respectively, from 0 to 50 m away from the road. The pollution maps show that the maximum depositions occur precisely along the road plan. The highest pollution levels of grasses of 23 ng Pd/g grass and 260 ng PAHs/g grass dry weight were recorded between 0 and 10 m on both sides of the road. Pollution maps should thus help to assess more precisely the impact of road traffic on food quality.

International audience; Platinum (Pt) and Palladium (Pd) are massively used in catalytic converters, emitted with exhaust fumes and deposited on roadsides in particle sizes. If they are ingested by ruminants grazing in agricultural fields located along roads they may enter the food chain. The objective of this study is to assess the potential transfer of Pt (PtCl2) and Pd (PdCl2) towards milk, tissues (muscle) and organs (kidney, liver and mammary gland). Three lactating goats received orally a single dose of 200 mg of Pd and 200 mg of Pt at the beginning of the experiment. The milk was collected each day during eight days. On the eighth day, organs and tissues were sampled to analyse the metal concentrations by ICP-MS (quantification limit of 0.25 ng/g for Pd and Pt, detection limit of 0.08 ng/g). The experiment demonstrated a significant transfer of Pd and Pt to kidney. The detected concentration was, respectively, of 73.9 ng/g DW and 268.5 n/g DW (factor 22 and factor 73 compared to the control kidney). The amounts of metals were : in the liver,18.1 ng/g DW for the Pd and 8.1 ng/g DW for the Pt, in the mammary gland, 14.9 ng/g DW fort the Pd and 2.5 ng/g DW for the Pt and in the muscle, 4.9 ng/g DW for the Pd and 0.6 ng/g DW for the Pt. The Pd concentration detected in milk was higher (from 5 ng/g DW to 9 ng/g DW) than in control milk but the transfer factor remained very low (0.02%). The Pt in milk could not be detected because it was below the quantification limit (

International audience; The aim of this study was to establish the transfer of phenanthrene, pyrene, and benzo[a]pyrene and their major hydroxylated metabolites to milk and to urine after a single oral administration (100 mg per animal of each compound) in 4 lactating goats. Detection and identification of the analytes (native compounds, 1-OH pyrene, 3-OH phenanthrene, 3-OH benzo[a]pyrene) were achieved using gas chromatography-mass spectrometry. Benzo[a]pyrene, phenanthrene, and pyrene were rapidly detected in the plasma stream, whereas 1-OH pyrene and 3-OH phenanthrene appeared later in plasma. These data suggest that pyrene and phenanthrene are progressively metabolized within the organism. Recovery rates of pyrene and phenanthrene in milk over a 24-h period appeared to be very low (0.014 and 0.006%, respectively), whereas the transfer rates of their corresponding metabolites were significantly higher: 0.44% for 1-OH pyrene and 0.073% for 3-OH phenanthrene. Recovery rates in urine were found to be higher (1 to 10 times) than recovery rates in milk. The 1-OH pyrene was found to be the main metabolite in urine as well as in milk. Thus, as has been established for humans, 1-OH pyrene could be considered as a marker of ruminant exposure to polycyclic aromatic hydrocarbons. Because 1-OH pyrene and 3-OH phenanthrene were measured in milk (unlike their corresponding native molecules), metabolites of polycyclic aromatic hydrocarbons should be taken into consideration when evaluating the safety of milk. Benzo[a]pyrene and 3-OH benzo[a]pyrene were (less than 0.005%) transferred to milk and urine in very slight amounts. This very limited transfer rate of both compounds suggests a low risk of exposure by humans to benzo[a]pyrene or its major metabolite from milk or milk products.

International audience; The impact of chronic exposure to polycyclic aromatic hydrocarbons (PAHs) on milk contamination was evaluated by oral administration of a mixture of fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo(k)fluorene, benzo(a)pyrene and benzo(g,h,i)perylene at 0.02 mg/kg to lactating goats for 28 days. We analysed PAHs and their major metabolites in milk by gas chromatography-mass spectrometry. The results evidence several major points: (1) benzo(k)fluorene, benzo(a)pyrene and benzo(g,h,i)perylene were not detected in the milk; (2) unexpectedly, the concentration of fluorene, phenanthrene, anthracene, fluoranthene, pyrene and chrysene did not change with time; (3) monohydroxylated PAH metabolites (-OH), namely 2-OH-fluorene, 3-OH-phenanthrene and 1-OH-pyrene were detected shortly after administration. The concentrations of 2-OH-fluorene and 3-OH-phenanthrene reached, respectively, maxima of 0.41 and 0.22 ng/mL during the first exposure week, whereas the concentration of 1-OH pyrene increased to reach a maximum of 0.97 ng/mL on day 14, then slightly decreased during the last two exposure weeks. Those findings suggest a lack of activation of a metabolism that could lead to an excretion of PAHs into milk under native forms. However, a slight increase in concentration could induce the metabolism, which should lead to an increase in the excretion of metabolites into the milk. In spite of the absence of a significant transfer of parent PAHs to milk, the appearance of metabolites in milk raises questions of their impact on human health.

International audience; The purpose of this study was to determine the feed to milk transfer of 17 PCDD/Fs and 18 PCBs in goats exposed to a 10-week long-term intake of contaminated hay collected in the vicinity of a hazardous municipal waste incinerator. The sum of PCDD/Fs and PCBs WHO-I-TEQ was found to be higher than 3 ng kg−1 of milk fat after the first experimental week. Carry-over rates (CORs) of PCDD/Fs and PCBs could be established at steady state conditions for each compound studied. For PCDD/Fs, 2,3,7,8-TCDD appeared as the compound having the highest COR (38.8%). Within dioxin-like-PCBs the highest COR were found at a similar level (higher than 80%) for PCBs 105, 118 and 157. Concerning indicator-PCBs, COR ranged from 5% (PCB 101) to more than 40% (PCBs 118, 153 and 180). The intensity of this transfer appeared to be a function of physico-chemical properties (chlorination or log Kow) of the molecules and their metabolic behaviour.

International audience; The aim of this study was to determine the transfer kinetics of soil-bound polycyclic aromatic hydrocarbons to milk in lactating cows. Soil (500 g/day) fortified with fluorene (104 g/g dry soil), phenanthrene (82 g/g), pyrene (78 g/g), and benzo[a]pyrene (33 g/g) was administered to three dairy cows via a rumen cannulas for 28 consecutive days. Parent compounds and their major metabolites in milk were measured using gas chromatography-mass spectrometry. Secretion of parent compounds in milk did not increase significantly (P > 0.05) over the control values measured before supply. Target monohydroxylated metabolites were not detected in control samples, but 2-hydroxy fluorene, 3-hydroxy phenanthrene, and 1-hydroxy pyrene were present in milk by the second day of dosing. The highest concentrations of metabolites in milk (31-39 ng/mL) were for 1-hydroxy pyrene at days 7 and 14 of dosing. The observed plateaus for 3-hydroxy phenanthrene and 2-hydroxy fluorene were lower (respectively, 0.69 and 2.79 ng/mL) but significantly increased in comparison to the control samples. Contrarily, 3-hydroxy benzo[a]pyrene was not detected in milk at any sampling time. These results suggested a notable metabolism of the parent compounds after their extraction from soil during the digestive transfer. Thus, the metabolization of fluorene and pyrene can lead to higher concentrations of metabolites than of parent compounds in milk. Despite the absence of a significant transfer of parent PAHs to milk, the appearance of metabolites raises the questions of their impact on human health

L’activité agricole est en interaction avec d’autres activités anthropiques potentiellement émettrices de Polluants Organiques Persistants (POP). Ces molécules posent des problèmes de transfert dans la chaîne alimentaire, notamment vers les produits animaux. Les POP sont caractérisés par une forte rémanence, une volatilité élevée et une lipophilicité marquée entraînant leur accumulation potentielle dans les tissus adipeux. Ce groupe de molécules potentiellement toxiques pour l’homme et l’environnement fait l’objet d’une attention internationale. L’objectif de cette synthèse est d’aborder le devenir de trois familles de composés POP, de type hydrocarbures polycycliques : les dioxines-furanes (PCDD/F), les polychlorobiphényls (PCB) et les hydrocarbures aromatiques polycycliques (HAP). Les résultats de recherche montrent une contamination significative des fourrages situés en zones exposées aux polluants par comparaison avec des zones isolées. Ils mettent également en évidence un transfert différentiel de ces molécules toxiques vers les matrices biologiques dont le lait, Human activities produce polluting compounds such as the Persistent Organic Pollutants group (POPs) which may interact with agriculture. These molecules raised concern about risk of transfer through the food chain via the animal product. The POPs are characterised by a strong persistence in the environment, a high volatility and a lipophilicity which lead to their accumulation in fat tissues. These compounds are enlisted in international conventions to organise the information about their potential toxicity for humans and the environment. The aim of this paper is to study transfer in the food chain of three groups of POPs: the dioxins-furans (PCDD/F), the polychlorobiphenyls (PCB) and the Polycyclic Aromatic Hydrocarbons (PAH). The results show that the contamination of fodder by these compounds is observed when they are exposed to emission sources compared to remote areas. They also show that a differential transfer of the molecules is detected towards biological matrices (milk)

To evaluate the risk of PAHs and dioxins transfer to humans several studies on dairy ruminant exposure and on intestinal absorption have been conducted. In order to assess PAHs feed-milk transfer, the transfer of three 14C-labelled PAHs (14C-phenanthrene, 14C-pyrene, 14C-benzo[a]pyrene) and 14C-2,3,7,8-TCDD has been studied after a single oral ingestion (2.6 × 106 Bq) to lactating goats. Radioactivity associated to the labelled PAHs and 2,3,7,8-TCDD has been detected in milk seven hours after the molecules administration. Cumulated part of ingested radioactivity recovered in milk after five days have reached a similar level after 103 h for 14C-phenanthrene and 14C-pyrene (1.5% and 1.9% respectively). 14C-benzo[a]pyrene did not appear significatively in milk (0.2% of ingested radioactivity). Transfer of 14C-2,3,7,8-TCDD to milk was higher than for PAHs, reaching 7.8% of ingested radioactivity. The bioavailability of PAHs and dioxins was assessed using two animal models. In one hand, we have characterized the in-vitro transfer of PAHs and dioxin through intestinal barrier using Caco-2 cells cultivated on permeable filters. In the other hand, we have described the specific arterial apparition profile of the studied micropollutants in growing pig. The in-vitro experiment showed that 14C-pyrene, 14C-phenanthrene, 14C-benzo[a]pyrene and 14C-2,3,7,8-TCDD were able to cross the intestinal barrier. 14C-phenanthrene was transported 1.1-, 1.8-, and 6.7-folds more than respectively 14C-pyrene, 14C-benzo[a]pyrene and 14C-2,3,7,8-TCDD after 6 h exposure. Regarding arterial apparition profiles, 14C arterial level from 14C phenanthrene was about 3 and 10 times more elevated than 14C level from 14-C-benzo[a]pyrene and 14C-TCDD respectively. These results can be related to the intestinal barrier transfer profile of the same molecules. The results presented in this paper contribute to give new insights on evaluation of the risk of PAHs and dioxins transfer to humans via the dairy ruminant. They particularly clarify the way by which organic micropollutants are transferred to milk and to living organisms during digestion and absorption.

Though polycyclic aromatic hydrocarbon (PAH) transfer through intestinal epithelium seems principally governed by transcellular diffusion, other mechanisms may interfere. Several studies suggest a PAH metabolism via CYP450, particularly in liver, but only few data are available regarding intestinal barrier. This in vitro work aimed at studying PAH metabolism and its consequences on the transfer in the intestinal epithelium according to molecule physicochemical properties. It used 14C-labeled benzo[a]pyrene, pyrene, and phenanthrene. Medium analysis proved a metabolism in intestinal cells for each PAH. Parallel metabolism appeared to play a positive role in the intestinal transfer of PAHs under different forms: 14C from benzo[a]pyrene, pyrene, and phenanthrene were respectively transferred 26, 4, and 2 times less when cells were incubated with CYP450 inhibitors. Generally speaking, the faster and the higher a PAH crosses intestinal barrier, the less metabolized it will be.

International audience; To assess PAH contamination pastures, grass and soil samples have been collected from 10 m (d1), 50 m (d2), and 150 m (d3) perpendicular to a French highway (70 000 vehicles per day) and at a control site in a rural area away from nearby contaminating sources. Total PAH concentration ranges from 767 ng/g dry weight to 3989 ng/g dry weight, according to the matrix and the distance from the highway. Distance is not a significant factor for PAH deposition on grass, while in soil it has an effect between d1 and d2 or d3. The total PAH concentration in highway samples is 8 times higher than in control site samples for grass and 7 to 4 times higher for soil. Fluoranthene, pyrene, and phenanthrene are the major PAHs in grass samples at the control site and the highway, but the concentrations are about 5 times higher near the highway. In soil samples collected near the highway, the values of concentrations between all compounds are not statistically different. PAH deposition on grass is linked to the physicochemical properties of the compounds, which lead to a specific distribution of each molecule (according to their volatility and the number of aromatic rings) while no specific behavior is revealed in soil.

International audience; Le long des autoroutes et des aéroports, les HAP produits par les rejets de véhicules peuvent se déposer sur l'herbe et le sol et entraîner des risques de contamination de la chaîne alimentaire via le ruminant. De l'herbe et du sol ont été prélevés au plus près du bord de la route (10 m) et de la piste de décollage (50 m). Les analyses ont détecté la présence des 16 HAP listés par l'agence américaine de la protection de l'environnement à la fois sur les deux sites de prélèvement et dans l'herbe et le sol. Le site de l'autoroute est environ quatre fois plus contaminé (188 ng/g DW pour l'herbe) que le site de l'aéroport (69 ng/g DW) et des composés cancérigènes sont présents aussi bien dans l'herbe que dans le sol. De plus, la part des composés à faible poids molculaire et à quatre et moins de quatre cycles est plus élevée dans l'herbe (36 %) que dans le sol où les composés à haut poids moléculaire et à plus de quatre cycles aromatiques représentent 86 % de la somme des HAP.

This paper gives an overview of the current in vivo methods used to evaluate nutritional quality of proteins. It present in the first part methods used to assess digestibility of proteins, the interest and constraints of portal measurements and finally questions regarding digestive interactions between alimentary nitrogen and endogenous nitrogen are discussed. The second part of this paper is focused on the presentation of a study which was aimed to determine 15N porto-arterial kinetics after ingestion of 15N labelled milk, yogurt or heat treated yogurt. It indicates an original method which combines 15N isotope protein labelling and postprandial porto-arterial measurements in growing pigs. 15N portal absorption in the growing pig were performed after ingestion of uniformly (0.2509 APE) labelled 15N milk (M), yogurt (Y) and heat treated yogurt (HY). The highest porto-arterial differences of 15N were found in the period between 30 min and 90 min after ingestion. Main absorption of nitrogen from M and HY occurs during the 0-120 min time period (about 74% for M and 68% for HY). For Y, a larger displayed absorption period over the 0-240 min time period was observed. 15N absorption rate is close to 75% for each studied milk product, suggesting that M, Y and HY deliver nearly the same amounts of nitrogen to the organism. These results also indicate that major part of proteins are absorbed within the 240 min postprandial period.

International audience; Polycyclic aromatic hydrocarbons (PAHs) and dioxins are lipophilic organic pollutants occurring widely in the terrestrial environment. In order to study the PAHs and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) transfer in the food chain, pigs have been fed with milk mixed either with 14C-phenanthrene, with 14C-benzo[a]pyrene or with 14C-TCDD. The analysis of portal and arterial blood radioactivity showed that both PAHs and TCDD were absorbed with a maximum concentration at 4–6 h after milk ingestion. Then, the blood radioactivity decreased to reach background levels 24 h after milk ingestion. Furthermore, the portal and arterial blood radioactivities were higher for phenanthrene (even if the injected load was the lowest) than these of benzo[a]pyrene or these of TCDD, in agreement with their lipophilicity and water solubility difference. Main 14C absorption occurred during the 1–3 h time period after ingestion for 14C-phenanthrene and during the 3–6 h time period for 14C-benzo[a]pyrene and for 14C-TCDD. 14C portal absorption rate was high for 14C-phenanthrene (95%), it was close to 33% for 14C-benzo[a]pyrene and very low for 14C-TCDD (9%). These results indicate that the three studied molecules have a quite different behaviour during digestion and absorption. Phenanthrene is greatly absorbed and its absorption occurs via the blood system, whereas benzo[a]pyrene and TCDD are partly and weakly absorbed respectively. However these two molecules are mainly absorbed via the portal vein.

Polycyclic aromatic hydrocarbons (PAHs), mainly formed by incomplete anthropogenic organic matter combustion, are ubiquitous in the environment. To assess milk PAH contamination sources, milk samples were collected from the tank milk at farms located near potential contaminating emission sources such as cementworks, steelworks, and motorways. PAH analyses were carried out by gas chromatography coupled to mass spectrometry. Eight PAHs were identified in milk: naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, fluoranthene, pyrene, and benzo[a]anthracene. For all potential contaminating sources, these eight PAHs were detected with similar profiles and at low concentrations except for fluorene and naphthalene, for which source-molecule interaction is pointed out.

International audience; Polycyclic aromatic hydrocarbons (PAHs) are lipophilic organic pollutants occurring widely in the terrestrial environment. To study the transfer of PAHs in the food chain, pigs have been fed with milk spiked either with [14C]phenanthrene or with [14C]benzo[a]pyrene. The analysis of blood radioactivity showed that both PAHs were absorbed with a maximum concentration at 5-6 h after milk ingestion, similar to fat metabolism. The blood radioactivity then decreased to reach background levels 24 h after milk ingestion. Furthermore, the blood radioactivity was higher for phenanthrene (even if the injected load was the lowest) than for benzo[a]pyrene, in agreement with their solubility difference. These findings suggest that milk fat and PAHs were absorbed during the same time period.