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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.

National audience; The current paper reviews current knowledge on the organic chemical contaminants that may be present in hen eggs. They originate either from veterinary drugs or feed additives, from pesticides used for cereals production or from persistent pollutants of the environment. Carry-over studies are carried out before veterinary drugs and additives are allowed. For these compounds, official surveys reveal concentrations that are barely over the maximal residues limits. Excessive concentrations may be detected only in cases of inappropriate use of veterinary drugs or of cross contamination during feed processing, especially for coccidiostats. Carry-over experiments are also conducted before allowing pesticides to be used for cereal production. Effective control against environmental contaminants for animals raised outdoors is not easy. In fact, concentrations of dioxins, furans and polychlorobiphenyls exceeding the maximum concentrations permitted in eggs have been rarely recorded. The worst cases arise in home-produced eggs, probably as a result of practices that stimulate ingestion of environmental matrices, especially soil. In order to prevent the risk of the presence of such contaminants in eggs, factors affecting soil ingestion in animals raised outdoors should be better understood, and the impact of soil on the carry-over of ingested contaminants to eggs should be quantified.; Le présent article fait le point sur les contaminants chimiques organiques potentiellement présents dans les œufs de poules pondeuses. Ils ont pour origine soit des médicaments vétérinaires, des additifs introduits dans les aliments, des pesticides utilisés pour la production des matières premières entrant dans l’alimentation des animaux ou encore des polluants rémanents de l’environnement. Les médicaments vétérinaires et additifs alimentaires font l’objet d’études strictes de transfert avant d’être autorisés et les résultats d’enquêtes ou de contrôles officiels montrent que les limites maximales de résidus sont très rarement dépassées dans les œufs. Les non conformités ont en général pour origine une utilisation inadéquate de la molécule, ou des contaminations croisées lors de la fabrication des aliments, notamment pour les anticoccidiens. Les pesticides utilisés pour la production de matières premières entrant dans l’alimentation des animaux font également l’objet d’une étude d’évaluation du risque de transfert avant leur autorisation. L’exposition des animaux aux contaminants de l’environnement est plus difficilement contrôlable, notamment dans les élevages en plein air, et des dépassements importants des teneurs maximales autorisées pour les dioxines, furanes ou polychlorobiphényles sont parfois rencontrés dans ce type d’élevage. Les cas les plus préoccupants émanent d’élevages de particuliers, dans lesquels certaines pratiques semblent favoriser l’ingestion de matrices, notamment de sol, en quantités importantes. Afin de prévenir le risque de transfert de ces contaminants, il est important d’évaluer l’impact de ces pratiques sur l’exposition des animaux et de quantifier l’impact de la matrice sol sur le transfert des contaminants ingérés vers l’œuf.

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.

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.

The main emission sources of Persistent Organic Pollutants (POPs) should be attributed to Human activities although certain natural events may also enhance their production. After emission, these compounds can be potentially transferred to the food chain via interactions with livestock systems. POPs are characterized by some volatility, strong persistence in the environment, and a high lipophilicity, which leads to their accumulation in fat tissues. These molecules have raised concern about the risk of transfer through the food chain via the animal product. POPs are listed in several international conventions dealing with their potential toxicity for humans and the environment. This paper synthesizes current information on dairy ruminant exposure to POPs and the risk of their transfer to milk. Five major families of POPs have been considered: the two groups of dioxins and furans (PCDD/Fs), the Poly Chloro Biphenyls (PCBs), the Polycyclic Aromatic Hydrocarbons (PAHs) and the emerging family of Poly-Bromo-Diphenyl-Ethers (PBDE). Dairy ruminants are mainly exposed to theses POPs by oral ingestion, other contamination ways are considered as minor. The contamination of roughage and soil by these compounds is observed when they are exposed to emission sources (steelworks, cement works, waste incinerators or motorways) compared to remote areas. Concentrations in soil can be higher than in plants, especially for very persistent halogened compounds. Highest concentrations of POPs in soil may be close to 1 μg per kg dry matter for PCDD/Fs and PBDEs, 100 μg/kg dry matter for indicator PCBs, 10 g/kg dry matter for PAHs. The contamination of milk by persistent organic pollutants depends on environmental factors, which are related to the rearing system (feeding system, access to contaminated soil or not, stage of lactation, udder health of the animals) and of the characteristics of the considered contaminants (their chemical properties like molecular weight, halogenations, lipophilicity and metabolic susceptibility). Established transfer rates to milk were lowest for PAHs (generally less than 1%), mainly due to other excretion pathway like urine but also to a certain proportion of metabolization. Transfer rates of halogenized compounds were generally higher: for PCBs the rate of transfer varies widely from 5% to 90%, and for the PCDD/Fs from 1% to 40%. Further studies should clarify the effect of hydroxyl-metabolites of PAHs on Human health and precise the transfer rates of PBDEs where only few data are available.

International audience; Interactions of phenantrene, anthracene, pyrene, chrysene, and benzo[a]pyrene (polyaromatic hydrocarbons) with model phospholipid membranes were probed using the Langmuir technique. The lipid monolayers were prepared using 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine, 1,2-dipalmitoyl-sn-glycero-3-phosphoglycerol, 1,2-dipalmitoyl-sn-glycero-3-phosphoserine, 1,2-myristoyl-sn-glycero-3-phosphoethanolamine, 1,2-dilauroyl-sn-glycero-3-phosphocholine, and cholesterol. Surface pressure and electrical surface potential were measured on mixed phospholipid/PAH monolayers spread on a pure water subphase. The morphology of the mixed monolayers was followed with Brewster angle microscopy. Polarization-modulation infrared reflection−absorption spectroscopy spectra obtained on DPPE/benzo[a]pyrene showed that the latter interacts with the carbonyl groups of the phospholipid. On the other hand, the activity of phospholipase A2 toward DLPC used as a probe to locate benzo[a]pyrene in the monolayers indicates that the polyaromatic hydrocarbons are not accessible to the enzyme. The results obtained show that all PAHs studied affect the properties of the pure lipid, albeit in different ways. The most notable effects, namely, film fluidization and morphology changes, were observed with benzo[a]pyrene. In contrast, the complexity of mixed lipid monolayers makes the effect of PAHs difficult to detect. It can be assumed that the differences observed between PAHs in monolayers correlate with their toxicity.

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; Along highways, platinum group elements (PGE: Pt, Pd and Rh) and polycyclic aromatic hydrocarbons (PAHs) produced by the vehicle traffic can be deposited on grass and soil, leading to a risk of contamination through the food chain via farm animals. We studied the deposition of platinum group elements and polycyclic aromatic hydrocarbons on ryegrass pots exposed along a highway with 65 000 vehicles per day for 90 days in summer and autumn. After this exposure period, the ryegrass pots were transferred to a remote area for 5 weeks. The Pt, Pd and Rh concentrations were determined in ryegrass samples using inductively coupled plasma mass spectrometry (ICP-MS) and PAHs were quantified by high-pressure liquid chromatography (HPLC). Our results show that Pd and Rh concentrations increased with time of exposure. Pd concentrations ranged from 1.5 to 6.8 ng/g dry weight (d.w.), Rh from 1.5 to 3 ng/g d.w. and Pt from 0.3 to 1.4 ng/g d.w. The total PAH concentrations varied from 6 to 175 ng/g d.w. PGE and PAH deposition on ryegrass near the highway occurred mainly for the first weeks of exposure. During the 5 weeks following the exposure, the levels and profiles of PAHs and PGE (except Rh) in highway grasses transferred to a remote area did not significantly decrease, suggesting a potential risk of contamination for dairy ruminants

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.

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)

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

Food seems to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs) and dioxins. In vivo studies showed a blood absorption of these xenobiotics after their ingestion. Our work aimed at studying the in vitro transfer of PAHs and dioxins through intestinal barrier. Caco-2 cells were cultivated on permeable filters to measure transepithelial permeability of (14)C labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin, benzo[a]pyrene, pyrene, and phenanthrene, which differed in their physicochemical properties. The results showed that the molecules were able to cross intestinal cell layers. All the molecules were detected associated with cells, even if the dioxin was the less uptaken compound. Phenanthrene appeared in basal media faster, and its level after a 6-h exposure was respectively 1.1, 2, and 7 times higher than pyrene, benzo[a]pyrene, and 2,3,7,8-tetrachlorodibenzo-p-dioxin levels. These findings suggest that intestinal epithelium plays a key role in selective permeability and then in bioavailibility of micropollutants.

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.

The aim of this study was to determine the tissue distribution of 17 PCDD/Fs following the chronic ingestion of contaminated milk in rats and to assess the "target tissue/milk" BioConcentration Factors (BCFs) of these molecules. Contaminated milk, collected in a polluted area, has been incorporated into the diet of male rats at a low dose (31 pg I-TEQ/day/rat). For this exposure, the accumulation of PCDD/Fs in target tissues (liver and adipose tissue) was limited, the tissue concentrations stabilising between 90 and 120 days of daily intake to levels close to 3 pg/g of tissue (all tissues and molecules combined). The tissue distribution seemed to be governed by the congeners properties and by the tissue characteristics. An increase in the chlorination degree of dioxins caused a decrease in their incorporation in the adipose tissue, and consequently of the BCF values. Moreover, the distribution of dioxins between hepatocytes and adipocytes differed: unlike the liver, the quantities of dioxins in the adipose tissue were significantly (P

Food would seem to be one of the main ways of animal and human contamination with polycyclic aromatic hydrocarbons (PAHs). In vivo studies suggest a transfer in intestinal epithelium by diffusion, which appears extensively governed by the physicochemical properties of PAHs, particularly lipophilicity. However, other mechanisms, such as metabolism, are considered to intervene. Our work aimed at testing in vitro intestinal metabolism and defining its impact on transepithelial transport of PAHs. Caco-2 cells were cultivated on permeable filters and incubated with 14C-labeled benzo[a]pyrene (BaP), pyrene (Pyr), and phenanthrene (Phe), which differ in their physicochemical properties. The results showed that the cells were able to metabolize the compounds. In basal media, Phe appeared to be the least hydroxylated molecule (45% after a 6-h exposure), followed by Pyr (65%) and finally BaP (96%). Inhibition of PAH metabolism showed a determinant effect on kinetics profiles. Transfer in the basal compartment of BaP, Pyr, and Phe radioactivities was, respectively, 26, 4, and 2 times lower with inhibitors, corroborating that intestinal metabolism of PAHs would have a positive impact on their transfer, an impact that increased with their lipophilicity. Furthermore, after a 6-h incubation, metabolites were also detected in apical medium. These findings suggested that intestinal metabolism might play a key role in intestinal barrier permeability and thus in the bioavailability of tested micropollutants.

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.

A continuous daily oral dose of (99)TcO(4)(-) (5 Bq g(-1) day(-1)) was given to young rats for 56 days. In one group the intake was continued for 98 days, while in the other the intake was stopped to facilitate the determination of biological half lives in different organs and tissues. The absorbed fraction of (99)Tc increased from 0.7 to 0.9 during the experimental period (m=0.85 sigma=0.02). The whole body retained fraction (m=0.15 sigma=0.05) indicated a storage in the tissues. The liver and kidneys showed increasing concentrations of (99)Tc until a plateau was reached after 6 and 9 weeks, then a rapid decline after the intake was stopped (half life of 6 and 5 days respectively). In hair and thyroid tissue, the accumulation of (99)Tc increased linearly then declined very slowly after the intake was stopped and did not reach a plateau during the experiment. No significant amounts of (99)Tc were detected in the muscular tissues or in the walls of the digestive tract. After the contamination period, urinary and fecal excretions fell off very quickly (1 week), but significant, though low, quantities of urinary and fecal excretions were still observed 6 weeks after stopping intake.

Polychlorodibenzo-para-dioxins (PCDDs) and Polychlorodibenzofurans (PCDFs) are ubiquitous in the environment. They are mainly formed as unwanted byproducts during various chemical, industrial, and combustion processes. Thus, these pollutants can be found in the food chain. The aim of this experiment was to study the transfer of PCDD/Fs from spiked milk to arterial blood in pigs, which are considered as valid models for humans. Pigs were fed with 900 mL of milk spiked with a mixture of 17 dioxins. The levels of PCDD/Fs in the serum extracts were determined using HRGC/HRMS prior to consumption of the milk, and at 3, 5, and 7 h after milk ingestion. Concentrations of PCDD/Fs in arterial plasma increased from 3 h to 5 h and decreased at 7 h. At time point 5 h, concentrations were found between 500 and 10 000 pg g -1 fat. The transfer ratio « plasma fat/milk fat » was usually found between 0.7 and 3%. Related to the different milk concentrations, results of this study indicate a similar behavior of the studied molecules.

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) 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.

The extracellular matrix, composed mainly of collagen, is considered responsible for the residual toughness of meat. Matrix metalloproteinases (MMP) responsible for the degradation of connective tissue are found in most tissues, but their participation in meat aging has not been tested. We recently showed that skeletal muscle has multiple MMP activities, as well as regulators and tissue inhibitors of metalloproteinases. Here we present the first observations of physiologic and postmortem variation of MMP activities in muscle. Growing lambs were offered two levels of intake: hay + concentrate for lambs with high growth rate (average daily gain > 250 g) and hay only for those with low growth rate (average daily gain < 25 g). At slaughter and at 21 d of postmortem aging of longissimus and semimembranosus muscles, we studied collagen content, collagen solubility, free hydroxyproline (OH-pro), and levels of latent and active forms of a matrix metalloproteinase (MMP-2) by gelatin zymography. Our results demonstrate the presence of an active isoform of MMP-2 in lamb muscle. Its level was higher (+90%, P < 0.01) in lambs that expressed a high growth rate. Activity of MMP-2 was also present at 21 d postmortem, at levels similar to those detected at slaughter. At slaughter and at 21 d, all muscles contained latent MMP-2 and the quantity of proenzyme was greater than that present in the activated form. The levels of free OH-pro in muscles of lambs with high growth rate increased significantly (P < 0.001) over 21 d from 3.75 to 5.08% of total collagen, and this was significantly related to the level of active MMP-2 at slaughter. By contrast, the amount of free OH-pro in muscles of lambs with low growth rate was not different at 21 d (1.63% of total OH-pro) than it had been at slaughter (1.84% of total OH-pro). These results suggest that collagen degradation all the way to free amino acids occurs postmortem in muscle and that there are active MMP simultaneously present that may account for this catabolism. The growth rate of animals at slaughter influences collagen turnover in vivo, as well as postmortem collagen degradation.

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.

Twenty-two 4-month-old lambs were used in two experiments to assess the effects of growth rate, induced by different feeding levels, and ageing (21 days, 4°C) on non-protein nitrogen (NPN) contents and their peptide composition. Muscle ( Longissimus dorsi , Semimembranosus ) and sex (male, female) effects were also studied. During ageing, NPN contents increased (15–20%). This variation represented 1.6–2.8% of total nitrogen. Peptides extracted from fresh muscles were in the range of molecular weight (MW) up to 12 kDa, the majority being less than 2.4 kDa (45–48%). During ageing, peptide average MW decreased (11.5–27.6%). High growth rate increased NPN contents at slaughter (+6–14%) and during ageing. Peptide average MW and post-mortem proteolysis rate as with to NPN variations were also higher. Differences between sex were observed at the end of the ageing period. Muscle effects were observed on the peptide class from 6.8 to 3.4 kDa.

Polycyclic aromatic hydrocarbon (PAH) levels were studied in grass and milk sampled at two farms, one located in a non-contaminated, rural area, and another located in a urban area close to PAH sources such as highways, busy roads, fuel-powered trains and a steel plant. PAH concentration were measured by gas chromatography coupled to mass spectrometry (GC-MS) using internal deuterated standards. In grasses, unexpectedly, although the sum of PAH concentrations was only slightly higher at the urban farm (83.1 ± 16.1 ng g−1) than the rural farm (51.8 ± 10.6 ng g−1), this difference was not observed for all PAH members. This absence of a striking difference of PAH levels between urban and rural grasses suggests that atmospheric PAH sources, for example, vehicle exhausts and chimney fumes, could be rapidly diluted by winds. In milk, PAH concentrations were not significantly different at urban and rural farms.

Ionic strength plays an important role in post mortem muscle changes. Its increase is due to ion release during the development of rigor mortis. Twelve alpine kids were used to study the effects of chilling and meat pH on ion release. Free ions were measured in Longissimus dorsi muscle by capillary electrophoresis after water extraction. All free ion concentrations increased after death, but there were differences between ions. Temperature was not a factor affecting ion release in contrast to ultimate pH value. Three release mechanisms are believed to coexist: a passive binding to proteins, which stops as pH decreases, an active segregation which stops as ATP disappears and the production of metabolites due to anaerobic glycolysis.

International audience

Objectives: Located in the city center and surrounded by many metal pollution sources, Gounti Yena valley is an important area of vegetable crops in Niamey. This study aims to determine the trace metals concentrations of plants grown in this valley. Methods and Results: Samples of lettuce ( Lactuca sativa) and cabbage ( Brassica oleracea) were collected from three sites selected according to their proximity to metal pollution sources. Trace metals concentrations in cabbage and lettuce were analyzed by inductively coupled plasma mass spectrometry (ICP-MS) after acid digestion. The results showed a significant accumulation of metals by cabbage and lettuce grown in Gounti Yena valley. The average metals concentrations reach 0.60, 3.73, 8.19, 2137.28, 2.85, 5.17 and 157.51 mg/kg DM, respectively, for cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) Conclusion and application of research: Detection of concentrations above permissible levels, in cabbage and lettuce of heavy metals like Cd, Cr, Fe, Zn and Pb especially, which have adverse effects on human health, requires further investigation on the causes of their transfer to grown plants. Adequate measures could then be taken by the competent authorities to limit or reduce the contamination of plants grown in the Gounti Yena valley., Située en plein centre ville et cernée par de nombreuses sources de pollution métallique, la vallée de Gounti Yena est l’une des principales zones de cultures maraîchères de la ville de Niamey. Cette étude a pour but de déterminer les teneurs en métaux des végétaux cultivés dans cette vallée. Méthodologie et résultats : Des prélèvements des échantillons de laitue (Lactuca sativa) et du chou (Brassica oleracea) ont été réalisés sur 3 sites retenus en fonction de leur proximité à des sources de pollution métallique. Les concentrations en éléments traces métalliques (ETM) des végétaux prélevés ont été analysées par spectrométrie de masse avec plasma à couplage inductif (ICP-MS) après digestion acide. Les résultats obtenus montrent une importante accumulation des ETM par le chou et la laitue cultivés dans la vallée de Gounti Yena. En effet, les teneurs moyennes en ETM atteignent 0,60; 3,73 ; 8,19 ; 2137,28 ; 2,85; 5,17 et 157,51 mg/kg MS respectivement pour cadmium (Cd), chrome (Cr), cuivre (Cu), fer (Fe), nickel (Ni), plomb(Pb), et zinc (Zn). Conclusion et application de la recherche : La détection dans le chou et la laitue des métaux comme Cd, Cr, Fe, Zn et surtout le Pb qui ont des effets néfastes sur la santé humaine, à des concentrations supérieures aux normes autorisées, pousse à rechercher les déterminants de leurs transferts vers les plantes cultivées. Des mesures adéquates pourront alors être prises par les autorités compétentes pour limiter ou réduire la contamination des végétaux évoluant dans cette vallée. Mots Clés: Contaminations, ETM, Végétaux, Normes, Gounti Yena, Niamey

The amounts of free amino-acids in Longissimus dorsi (LD), Triceps brachii (TB) and Rectus femoris (RF) from 8 Friesian 20-month old bulls were determinated using gas chromatography. The amounts of free amino-acids released during storage from 3 to 14 days post mortem at 4 °C depended on the muscle. Total free hydroxyproline in LD increased from 3% at 3 days to 11% at 14 days post mortem. Free amino-acids seemed to increase more after 10 days than between 3 and 10 days post mortem. The myofibrillar fragmentation index was highly correlated with leucine, isoleucine, threonine and methionine contents in TB and RF. MFI was correlated with hydroxyproline, leucine and isoleucine in LD.

International audience; Organic pollutants like PAHs, PCDD/Fs and PCBs can be transferred to the milk of lactating goats after an oral contamination. This study focused on the effects of an oral chronic administration of milk issued from these goats on brain metabolism and behaviour in adult rats. Four groups of rats (n = 12) were treated with methylcellulose 0.3% (MC), non-contaminated milk (NCGM), contaminated milk with PAHs or with a PCDD/F-PCB mixture (PCM). MC or milk were daily administrated during 3 weeks (0.5 ml/100 g bw, p.o.). At the end of the treatment, rats were studied for their locomotor, spatial memory and anxiety performances in an open-field, a T maze and an elevated plus maze (EPM), respectively. Thus, the animals were sacrificed, the brain removed and the tissue analyzed for fingerprinting using the 1H NMR spectroscopy. Urine samples were also collected once a week over the treating period. The multivariate statistical analysis of the 1H NMR spectra of urine discriminated PAH- and PCM-treated animals from controls (MC, NCGM) after 3 weeks of treatment. At the same time, PAH-treated rats exhibited a reduction of the anxiety-related behaviour in the EPM and deficits of spontaneous alternation in the T maze whereas the PCM animals did not. In the brain, PAHs and PCM induced metabolic deviations compared to controls, but these perturbations were different between the two contaminated groups. These results suggest differences in the neurotoxicity of xenobiotics from one group of pollutants to another, and question the toxicity of these compounds through ingestion of contaminated food.

Les hydrocarbures aromatiques polycycliques ont récemment défrayé la chronique à plusieurs reprises. Cet article se propose de faire le point sur les propriétés de ces molécules en vue de donner un aperçu des voies pour la recherche d’outils d’évaluation et de gestion des risques liés à ces molécules. De nombreuses molécules peuvent prétendre appartenir à cette famille. Nous traiterons de celles les plus communément impliquées dans les problèmes de sécurité alimentaire, à savoir la famille des dioxines-furanes ou polychloro-dibenzo-paradioxines/furanes (PCDD/F), celle des composés polychlorés biphényles (PCB) et enfin celle des hydrocarbures aromatiques polycycliques (HAP) que nous réserverons dans ce texte aux composés non chlorés.

National audience

Séance : Qualité des produits; International audience; This article critically reviews the state of knowledge on the quality of animal-source foods according to animal production and food processing conditions, including consumesafety, commercial, sensory, nutritional, technological, convenience, and image. Image covers ethical, cultural and environmental dimensions associated with the origin of the food and the way it is produced and processed. This framework enables to highlight the priorities given to the different quality attributes. It also helps to identify potential antagonisms and synergies among quality attributes, between production and processing stages, and among stakeholders. Primacy is essentially given to commercial quality attributes, especially for standard-commodity animal-source foods. This primacy has strongly influenced genetic selection and farming practices in all livestock commodity chains and enabled substantial quantitative gains, although at the expense of other quality traits. Focal issues are the destructuration of chicken muscle that compromises sensory, nutritional and image quality attributes, and the fate of males in the egg and dairy sectors, which have heavily specialized their animals. Quality can be gained but can also be lost throughout the farm-to-fork continuum. Our review highlights critical factors and periods throughout animal production and food processing routes, such as on-farm practices, notably animal feeding, pre-slaughter and slaughter phases, food processing techniques, and food formulation. It also reveals on-farm and processing factors that create antagonisms among quality attributes, such as the castration of male pigs, the substitution of marine-source feed by plant-based feed in fish, and the use of sodium nitrite in meat processing. These antagonisms require scientific data to identify trade-offs among quality attributes and/or solutions to help overcome these tensions. There are also food products that value synergies between quality attributes and between production and processing phases, particularly Geographical Indications. Human epidemiological studies have found associations between consumption of animal-source foods and increased or decreased risk for chronic non-communicable diseases. These associations have informed public health recommendations. However, they have not yet considered animal production and food processing conditions. A concerted and collaborative effort is needed from scientists working in animal science, food process engineering, consumer science, human nutrition and epidemiology in order to address this research gap. Avenues for research and main options for policy action are discussed.r expectations-behaviours and the effects of consumption of animal-source foods on human health. Quality has been defined through seven core attributes:; Cette synthèse dresse un bilan critique de l'état des connaissances sur la qualité des aliments d'origine animale selon les conditions de production de l’animal et de transformation des produits, y compris les attentes et comportements des consommateurs et les effets de la consommation des aliments sur la santé humaine. La qualité a été déclinée selon sept dimensions : sanitaire, commerciale, organoleptique, nutritionnelle, technologique, d’usage et d’image. Cette dernière recouvre les dimensions éthiques, culturelles et environnementales associées à l'origine de l'aliment et à la manière dont il a été élaboré. Ce cadre permet de mettre en évidence les priorités accordées à ces différentes dimensions et d'identifier les antagonismes et synergies potentiels entre elles. Nous faisons un constat de priorité accordée aux dimensions commerciales de la qualité, notamment pour les produits standards. Cette priorité a fortement orienté la sélection génétique des animaux et les pratiques d’élevage dans toutes les filières. Elle a permis des gains quantitatifs considérables, mais souvent au détriment d'autres dimensions de la qualité. Des exemples emblématiques sont le poulet de chair standard, pour lequel la sélection sur la vitesse de croissance et le rendement en filet ont eu des conséquences délétères sur les propriétés organoleptiques, nutritionnelles et d'image, et le devenir des mâles dans la filière poules pondeuses ; et certaines filières laitières, qui ont fortement spécialisé leurs animaux. La qualité peut se construire mais aussi s’altérer tout au long de la chaîne alimentaire. Nous soulignons les facteurs et les périodes critiques, comme les pratiques d’élevage, notamment l'alimentation des animaux, les phases de pré-abattage et d'abattage, les pratiques de transformation et de formulation des aliments. Nous pointons certains facteurs qui créent des antagonismes entre différentes dimensions de la qualité, comme la castration des porcs mâles, la substitution des aliments d'origine marine par des aliments d'origine végétale chez les poissons, et l'utilisation des nitrites dans la transformation de la viande. Les recherches s’orientent vers les possibles compromis entre ces effets positifs et négatifs et/ou vers des solutions pour dépasser ces antagonismes. Il y a aussi des aliments qui valorisent des synergies entre différentes dimensions de la qualité et entre les phases de production et de transformation, notamment les indications géographiques. Les études d’épidémiologie nutritionnelle montrent des associations entre la consommation d'aliments d'origine animale et l'augmentation ou la diminution du risque de maladies chroniques ; elles ont permis de formuler des recommandations en matière de santé publique. Cependant, elles ne prennent pas encore en compte les conditions de production et de transformation, et nous pointons le besoin d’une meilleure connexion entre les communautés scientifiques à l’échelle de l’élevage, de la transformation, de la nutrition humaine et de l'épidémiologie pour combler cette lacune. Les besoins de recherche et les pistes d'action publique sont discutés.

International audience; Depuis une dizaine d’années, de nombreuses études questionnent notre consommation d’aliments d’origine animale. Les impacts de l’élevage sur l’environnement, les effets sur la santé humaine d’une consommation excessive de viande rouge et de charcuterie ainsi que les préoccupations d’éthique envers les animaux ont fait évoluer l’image de ces produits. Peu de travaux ont cependant analysé leur qualité dans ses différentes dimensions. C’est ce que propose cet ouvrage qui reprend les principaux enseignements d’une expertise scientifique collective coordonnée par INRAE en 2020. Il caractérise conjointement les propriétés organoleptiques, nutritionnelles, sanitaires, technologiques, commerciales, d’usage et d’image de ces aliments.Embrassant toute la chaîne de fabrication de l’aliment, il pointe les facteurs d’élevage et de transformation influant sur la qualité et souligne les possibles antagonismes ou synergies entre les dimensions de la qualité et entre les différentes étapes de l’élaboration du produit. Les auteurs comparent, par ailleurs, les engagements spécifiques des produits bénéficiant de signes de qualité (bio, Label rouge, AOP, IGP, STG).

A fast and efficient multiresidue extraction-purification procedure was developed for low levels (ppb range) of phenanthrene and hydroxyphenanthrene in biological matrices, in order to quantify phenanthrene and metabolites in blood, milk, urine, and biological tissues of lactating goats. Detection and identification of the analytes (phenanthrene and 1-, 2-, 3-, 4-, and 9-hydroxyphenanthrene) were achieved using gas chromatography coupled to mass spectrometry. Deuterium-labeled phenanthrene was used as internal standard for phenanthrene and 2-OHfluorene for metabolites. The developed method includes enzymatic hydrolysis, liquid-liquid extraction, and Envi-Chrom P SPE column purification. Analyses were performed in the selected ion monitoring mode to achieve ad hoc sensitivity in accordance with analyte concentrations in food samples. Detection limits were between 2.3 and 5.1 ng/mL (ppb) for milk samples, 0.5 and 2.5 ng/mL for urine and blood samples, and 1.9 and 8.0 ng/g for tissue samples. This original multiresidue and multimatrix analytical methodology was applied to metabolism studies and polycyclic aromatic hydrocarbon (PAH) risk assessment. We demonstrated, for the first time, that metabolites were present in milk. These results suggested that usual PAHs analysis methods based on the detection of native molecule are not representative of the real contamination of biological matrices.

The use of chlordecone (CLD), an organochlorine pesticide used in the French West Indies banana fields between 1972 and 1993, resulted in a long-term pollution of agricultural areas. Animals may be exposed to CLD by ingesting contaminated food or environmental matrices (soil, water or plants). This PhD project is integrated in the objective of securing animal sectors against CLD risk.The aims of this thesis are (1) to provide knowledge on distribution and elimination mechanisms of CLD in farm animals and (2) to develop decision support tools to assist local animal sectors. To this end, in vivo experiments were performed in adult ewes and growing pigs. In pigs, two experiments consisting of monitoring serum and fecal elimination kinetics following a single intravenous administration of CLD or CLDOH (chlordecol) were performed. Non-compartmental and compartmental approaches were used to estimate toxicokinetic parameters of CLD and its metabolites from serum kinetics. Faecal kinetics were used to characterize metabolism of CLD and to quantify its faecal excretion. In ewes, these toxicokinetic data were already available in literature, so the objective was to complete them by characterizing CLD distribution. An experiment involving sequentially slaughters during contamination and decontamination phases allowed to characterize the distribution dynamics of CLD. Correlations between concentrations in tissues were established and CLD half-lives in tissues were calculated. The monitoring of fecal kinetics provided additional knowledge on CLD excretion. All toxicokinetic results obtained in ewes were used to develop a physiologically based pharmacokinetic (PBPK) model to predict CLD concentrations in various tissues. This model will be used to develop decision support tools to assist animal sectors in CLD contaminated areas. An in vivo study is being considered in pigs to characterize the dynamics of CLD tissue distribution and thus be able to develop similar tools to those developed in ewes., L’utilisation de la chlordécone (CLD), un pesticide organochloré utilisé dans les bananeraies des Antilles Françaises de 1972 à 1993, a conduit à une pollution durable des surfaces agricoles. En ingérant des aliments ou des matrices environnementales (sol, eau ou végétaux) contaminés, les animaux sont susceptibles d’être exposés à la CLD. Ces travaux de thèse s’intègrent dans l’objectif de sécurisation des filières animales vis-à-vis du risque CLD. Les objectifs de cette thèse sont (1) d’apporter des connaissances sur les mécanismes de distribution et d’élimination de la CLD chez les animaux d’élevage et (2) de développer des outils d’aide à la décision pour accompagner les filières animales locales. Pour cela, des expérimentations in vivo ont été réalisées chez le porc en croissance et la brebis adulte. Chez le porc, deux expérimentations consistant à suivre les cinétiques d’élimination sérique et fécale suite à une administration intraveineuse en dose unique de CLD ou de CLDOH (chlordécol) ont été réalisées. Des approches non compartimentales et compartimentales ont été utilisées pour estimer les paramètres toxicocinétiques de la CLD et de ses métabolites à partir des cinétiques sériques. Les cinétiques fécales ont permis de caractériser le métabolisme de la CLD et de quantifier son excrétion fécale. Chez la brebis, l’ensemble de ces données toxicocinétiques étant déjà disponibles dans la littérature, l’objectif était de les compléter en caractérisant la distribution de la CLD. Une expérimentation impliquant des abattages sériés pendant une phase de contamination et de décontamination a permis de caractériser la dynamique de distribution de la CLD. Des corrélations de concentrations entre les tissus ont ainsi été établies et des temps de demi-vies tissulaires ont été calculés. Le suivi de la cinétique fécale a également permis de compléter les connaissances sur l’excrétion de la CLD. L’ensemble des résultats toxicocinétiques obtenus chez la brebis ont été utilisés pour développer un modèle pharmacocinétique à base physiologique (PBPK) permettant de prédire les concentrations de CLD dans différents tissus. Ce modèle servira de base pour l’élaboration d’outils d’aide à la décision pour accompagner les filières animales dans les zones contaminées par la CLD. Une étude in vivo est envisagée chez le porc pour caractériser la dynamique de distribution tissulaire et ainsi pouvoir développer des outils similaires à ceux construits chez la brebis.

The contamination of agricultural soils by chlordecone threatens the sustainability of outdoor farming in the West Indies. In order to maintain the latter while protecting consumers of terrestrial animal products, several strategies are being studied. This thesis is focused on one of them which consists of sequestering chlordecone in order to significantly reduce its bioavailability for the animal. The experimental approach was carried out in stages, based on three pillars: biochar or activated carbon as sequestering materials, the use of artificial soils and the concept of relative bioavailability to assess sequestration performance. Tests conducted with activated charcoal (based on dates kernels, coconut or lignite) have shown that chlordecone is sequestered in an aqueous medium or in animals, but for the latter it only works if chlordecone and sequestering matrix had a prolonged contact time (or maturation) with ingestion by the animal. These results show the interest of in situ sequestration, ie directly in the contaminated soil likely to be ingested by the animals. As activated charcoal has a high cost, a priori less expensive carbonaceous materials have been tested: biochars based on various wood species. These biochars produced at two pyrolysis temperatures (500 and 700 ° C) were characterized from a physical point of view (porosity) and selected via an in vitro environmental availability test. In vivo tests (on piglets) did not show that these selected biochars were able to effectively sequester chlordecone, since the relative bioavailability was not different from one (reference = standard soil without organic matter). The presence of peat in the artificial soil does not prevent trapping by exogenous carbonaceous matrices. The in vitro test used and the in vivo test give equivalent tendencies to reduce the relative bioavailability, which is interesting in a logic of validation of the in vitro test. These positive results show that the strategy of sequestration by highly carbonaceous materials is possible, requires properties of microporosity and access to pores close to those of an activated carbon, but contingent on the experimental conditions implemented, they must be continued and validated on natural soils, La contamination des sols agricoles par la chlordécone menace la durabilité de l’élevage de plein air aux Antilles. Afin de maintenir ce dernier tout en protégeant les consommateurs de denrées animales d’origine terrestre, plusieurs stratégies sont étudiées. Ces travaux de thèse sont focalisés sur l’une d’entre elles qui consiste à séquestrer la chlordécone afin de réduire significativement sa biodisponibilité pour l’animal. La démarche expérimentale a été réalisée par étape, elle s’appuie sur trois piliers : des matières séquestrantes carbonées de type biochar ou charbon activé, l’utilisation de sols artificiels et sur le concept de biodisponibilité relative pour évaluer les performances de séquestration. Les essais conduits avec du charbon activé (à base de noyaux de dattes, de coco ou de lignite) ont montré une séquestration de la chlordécone en milieu aqueux ou chez l’animal, mais pour ce dernier cela ne fonctionne que si la chlordécone et la matrice séquestrante ont eu un temps de contact prolongé (ou maturation) avec l’ingestion par l’animal. Ces résultats montrent l’intérêt d’une séquestration in situ, à savoir directement dans le sol contaminé susceptible d’être ingéré par les animaux. Comme le charbon activé a un coût élevé, des matières carbonées a priori moins coûteuses ont été testées : des biochars à base de diverses essences de bois. Ces biochars produits à deux températures de pyrolyse (500 et 700°C) ont été caractérisés d’un point de vue physique (porosité) et sélectionnés via un test in vitro de disponibilité environnementale. Les tests in vivo (sur porcelets) n’ont pas montré que ces biochars sélectionnés étaient aptes à séquestrer efficacement la chlordécone, puisque la biodisponibilité relative n’était pas différente de un (référence = sol standard sans matière organique). La présence de tourbe dans le sol artificiel ne s’oppose pas au piégeage par les matrices carbonées exogènes. Le test in vitro utilisé et le test in vivo donnent des tendances équivalentes de réduction de la biodisponibilité relative, ce qui est intéressant dans une logique de validation du test in vitro. Ces résultats positifs montrent que la stratégie de séquestration par des matériaux hautement carbonés est possible, requiert des propriétés de microporosité et d’accès aux pores proches de celles d’un charbon activé, mais contingents des conditions expérimentales mises en œuvre ils doivent être poursuivis et validés sur des sols dits naturels

In the Lorraine Region, about 7,000 ha of ponds are exploited for fish production. The present work was dedicated to the understanding of micropollutants transfer mechanisms in freshwater fishponds focusing on three issues: (1) evaluate the extent of fishpond (n=45) exposure to trace metals (2) evaluate the influence of fishponds (n=3) on concentrations, potential toxicity and mass flows of pesticides; (3) evaluate the relative importance of transfer pathways of PCBs to fish. (1) The enrichments measured were generally low to moderate with the exception of the sites located in the Vôge and two sites located in the Woëvre. Enrichment was particularly high for Cd and seemed related to the loss of ignition. No relationship between enrichment and land use could however be observed. (2) High pesticide concentrations were generally reduced by more than 90% between upstream and downstream location. The risk of toxicity, evaluated under the toxic unit approach was attenuated downstream of the ponds. When considering the flow of pesticides, the results suggest that, depending on the substances in question, 10 to 100% of the loads of pesticides are retained in fishponds. (3) The oral transfer of polychlorinated biphenyls (PCBs 138, 153, and 180) from a contaminated sediment to a benthic fish (carp) was studied by the in vivo relative bioavailability method. The results show that the contaminated sediment has no effect on the oral bioavailability of the three PCB congeners in common carp. The geosorbing effect of sediment, which explains its role as an environmental reservoir of PCBs, seems insufficient under the conditions of the digestive tract of the common carp, to prevent transfer to fish, En Lorraine, environ 7000 ha d’étangs sont exploités pour la production piscicole. Le présent travail a été consacré à la compréhension des mécanismes de transfert des micropolluants dans les étangs en mettant l'accent sur trois questions : (1) évaluer l'ampleur de la contamination métallique des étangs (n=45) ; (2) évaluer l'influence des étangs (n=3) sur les concentrations, le risque de toxicité et les flux de pesticides; (3) évaluer l'importance relative des voies de transfert des PCB vers le poisson. (1) Les enrichissements calculés soulignent des contaminations généralement faibles à modérés à l’exception des étangs localisés dans la Vôge et de deux étangs localisés dans la Woëvre. Cet enrichissement est plus prononcé pour le Cd et semble être lié à la richesse du sédiment en matière organique et carbonates (perte au feu). (2) Dans les cours d’eau de tête de bassin versant sur lesquels s’inscrivent ces trois étangs de barrage, les concentrations les plus élevées étaient généralement réduites de plus de 90% entre l'amont et l'aval de l'étang. Le risque de toxicité, évalué par la méthode de l'unité toxique, était atténué en aval des étangs. Lorsqu’on considère les flux de pesticides, les résultats obtenus suggèrent que, selon les substances considérées, les charges en pesticides sont réduites de 10 à 100% entre l'amont et l'aval de l'étang. (3) Les résultats montrent que le sédiment contaminé n’a pas d’impact sur la biodisponibilité orale des trois congénères de PCB chez la carpe commune. L’effet géosorbant du sédiment, qui explique son rôle de réservoir environnemental de PCB, paraît insuffisant dans les conditions du tractus digestif de la carpe commune, pour éviter un transfert vers le poisson