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Humans are widely exposed to semivolatile organic contaminants in indoor environments. Many contaminants have long lifetimes following partitioning to the large surface reservoirs present indoors, which leads to long exposure times to gas-phase oxidants and multiphase chemistry. Studies have shown selective multiphase oxidation of organics on indoor surfaces, but the presence of hydroxyl radicals with nonselective reactivity and evidence of multiphase OH radical reactivity toward common indoor contaminants indicates that there may be additional unknown transformation chemistry indoors. We screened genuine indoor samples for 60 OH radical oxidation products of the common plasticizer and endocrine-disrupting contaminant bis(2-ethylhexyl) phthalate (DEHP) identified in laboratory experiments using nontargeted high-resolution mass spectrometry. At least 30 and 10 of these products are observed in indoor dust and DEHP films exposed to ambient indoor conditions, respectively, indicating that multiphase OH reactions occur indoors. Using the PROTEX model and a multimedia indoor chemical fate model, we demonstrate that these products have long indoor lifetimes and cause a higher potential for human exposure than DEHP. Some of these products are more active endocrine disruptors than DEHP itself, but most have unknown toxicities. Coexposure to all oxidation products will likely have an additive effect, leading to higher human health risks from indoor organic contaminants than previously thought. Due to the nonselective reactivity of OH radicals, it is likely that most indoor contaminants follow similar chemistry, and further study is needed to understand the prevalence and human health implications of such multiphase chemistry. [ABSTRACT FROM AUTHOR]

Introduction: Tire and road wear particles are one of the most abundant types of microplastic entering the environment. The toxicity of tire and road wear particles has been linked to their organic additives and associated transformation products. Tire and road wear particles, and associated tire-derived compounds are introduced to the agricultural environment via atmospheric deposition, irrigation with reclaimed wastewater, and the use of biosolids (treated sewage sludge) as fertilizer. In the agricultural environment, these tire-derived compounds could be taken up by edible plants, leading to human exposure. Methods: Sixteen tire-derived compounds were measured in twenty-eight commercial leafy vegetable samples from four countries. Based on the results, the estimated daily intake of these tire-derived compounds was calculated due to leafy vegetable consumption based on local diets under a mean and maximum concentration scenario. Results: In commercial leafy vegetables, six tire-derived compounds were detected: benzothiazole (maximum concentration--238 ng/g dry weight), 2-hydroxybenzothiazole (maximum concentration--665 ng/g dry weight), 1,3-diphenylguanidine (maximum concentration--2.1 ng/g dry weight), N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD, maximum concentration--0.4 ng/g dry weight), N-Isopropyl-N-phenyl-4-phenylenediamine (IPPD, maximumconcentration--0.1 ng/g dry weight), and N-phenyl-N-cyclohexylp-phenylenediamine (CPPD, maximumconcentration--0.3 ng/g dry weight). At least one compound was present in 71% of samples analyzed. The estimated daily intake for 1,3-diphenylguanidine ranged from 0.05 ng/person/day in the mean scenario to 4.0 ng/person/day in the maximum scenario; benzothiazole ranged from 12 to 1,296 ng/person/day; 6PPD ranged from 0.06 to 2.6 ng/person/day; IPPD ranged from 0.04 to 1.1 ng/person/day; CPPD ranged from 0.05 to 2.6 ng/person/day. Discussion: Statistical analyses did not reveal correlation between known growth conditions and tire-derived compound concentrations in the leafy vegetable samples. The estimated daily intake via leafy vegetable consumption was generally lower than or comparable to the estimated daily intake via other known sources. However, we show that tire-derived compounds are taken up by foodstuff, and exposure might be higher for other produce. Future studies are needed to uncover pathways of tire-derived compounds from road to food, assess the exposure to transformation products, and investigate the biological effects associated with this exposure. [ABSTRACT FROM AUTHOR]

Disinfection by-products (DBPs) are a concern due to their presence in chlorinated wastewater, sewage treatment plant discharge, and surface water, and their potential for environmental toxicity. Despite some attention to their ecotoxicity, little is known about the phytotoxicity of DBPs. This study aimed to evaluate the individual and combined phytotoxicity of four trihalomethanes (THMs: trichloromethane (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and tribromomethane (TBM) and their mixture (THM4)), and trichloroacetic acid (TCAA) using genotoxic and cytotoxic assays. The analysis included seed germination tests using Vigna radiata and root growth tests, mitosis studies, oxidative stress response, chromosomal aberrations (CA), and DNA laddering using Allium cepa. The results showed a progressive increase in root growth inhibition for both plant species as the concentration of DBPs increased. High concentrations of mixtures of four THMs resulted in significant (p < 0.05) antagonistic interactions. The effective concentration (EC50) value for V. radiata was 5655, 3145, 2690, 1465, 3570, and 725 mg/L for TCM, BDCM, DBCM, TBM, THM4, and TCAA, respectively. For A. cepa, the EC50 for the same contaminants was 700, 400, 350, 250, 450, and 105 mg/L, respectively. DBP cytotoxicity was observed through CAs, including C-metaphase, unseparated anaphase, lagging chromosome, sticky metaphase, and bridging. Mitotic depression (MD) increased with dose, reaching up to 54.4% for TCAA (50–500 mg/L). The electrophoresis assay showed DNA fragmentation and shearing, suggesting genotoxicity for some DBPs. The order of phytotoxicity for the tested DBPs was TCAA > TBM > DBCM > BDCM > THM4 > TCM. These findings underscore the need for further research on the phytotoxicity of DBPs, especially given their common use in agricultural practices such as irrigation and the use of sludge as manure. [ABSTRACT FROM AUTHOR]

IntroductionTire and road wear particles are one of the most abundant types of microplastic entering the environment. The toxicity of tire and road wear particles has been linked to their organic additives and associated transformation products. Tire and road wear particles, and associated tire-derived compounds are introduced to the agricultural environment via atmospheric deposition, irrigation with reclaimed wastewater, and the use of biosolids (treated sewage sludge) as fertilizer. In the agricultural environment, these tire-derived compounds could be taken up by edible plants, leading to human exposure.MethodsSixteen tire-derived compounds were measured in twenty-eight commercial leafy vegetable samples from four countries. Based on the results, the estimated daily intake of these tire-derived compounds was calculated due to leafy vegetable consumption based on local diets under a mean and maximum concentration scenario.ResultsIn commercial leafy vegetables, six tire-derived compounds were detected: benzothiazole (maximum concentration—238 ng/g dry weight), 2-hydroxybenzothiazole (maximum concentration—665 ng/g dry weight), 1,3-diphenylguanidine (maximum concentration—2.1 ng/g dry weight), N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD, maximum concentration—0.4 ng/g dry weight), N-Isopropyl-N-phenyl-4-phenylenediamine (IPPD, maximum concentration—0.1 ng/g dry weight), and N-phenyl-N-cyclohexyl-p-phenylenediamine (CPPD, maximum concentration—0.3 ng/g dry weight). At least one compound was present in 71% of samples analyzed. The estimated daily intake for 1,3-diphenylguanidine ranged from 0.05 ng/person/day in the mean scenario to 4.0 ng/person/day in the maximum scenario; benzothiazole ranged from 12 to 1,296 ng/person/day; 6PPD ranged from 0.06 to 2.6 ng/person/day; IPPD ranged from 0.04 to 1.1 ng/person/day; CPPD ranged from 0.05 to 2.6 ng/person/day.DiscussionStatistical analyses did not reveal correlation between known growth conditions and tire-derived compound concentrations in the leafy vegetable samples. The estimated daily intake via leafy vegetable consumption was generally lower than or comparable to the estimated daily intake via other known sources. However, we show that tire-derived compounds are taken up by foodstuff, and exposure might be higher for other produce. Future studies are needed to uncover pathways of tire-derived compounds from road to food, assess the exposure to transformation products, and investigate the biological effects associated with this exposure.

Consumption of locally caught fish provides health benefits but can be a route of exposure to methylmercury and other persistent environmental contaminants. Previous studies found that Asian women of childbearing age (WCBA) in the Milwaukee area have high levels of exposure through fish consumption but limited awareness of fish advisories. We conducted a focus group project to understand the influence of culture, attitudes, and beliefs on the fish consumption habits of Chinese, Hmong, and Karen WCBA who reside in the Milwaukee area to develop culturally appropriate educational materials.A total of 19 women aged 18–50 years identifying as Chinese, Hmong, or Karen were recruited. Three focus groups were held, each consisting of 6–7 participants from one ethnicity. Focus group transcripts were thematically analyzed and coded based on the integrated behavioral model.Nutritional benefits and availability were the most common reasons to eat locally caught fish. All participants were aware of risks associated with eating fish, yet few knew ways to mitigate risk and maximize benefits. Participants expressed interest in receiving health messages from trusted sources and recommended that messaging target families rather than just individuals. Participants who were confident in their self-efficacy expressed a greater likelihood of following health message guidelines.Results suggest providing culturally appropriate educational materials in preferred languages to Asian communities via local community organizations may increase self-efficacy and adherence to fish advisories. Future projects will evaluate the effectiveness of self-affirmation messaging among Asian WCBA and assess changes in fish consumption based on message content.

Children are regularly exposed to chemical contaminants that may influence brain development. However, relatively little is known about how these contaminants impact the developing human brain. Here, we combined silicone wristband exposure assessments with neuroimaging for the first time to examine how chemical contaminant mixtures are associated with the developing basal ganglia—a brain region key for the healthy development of emotion, reward, and motor processing, and which may be particularly susceptible to contaminant harm. Further, we examined demographic disparities in exposures to clarify which children were at highest risk for any contaminant-associated neurobiological changes. Participants included 62 community children (average age 7.00 years, 53% female, 66% White) who underwent structural neuroimaging to provide data on their basal ganglia structure and wore a silicone wristband for seven days to track their chemical contaminant exposure. 45 chemical contaminants—including phthalates and their alternatives, brominated flame retardants, organophosphate esters, pesticides, polycyclic aromatic hydrocarbons, and polychlorinated biphenyls—were detected in over 75% of wristbands. Notable demographic disparities in exposure were present, such that Non-White and lower-income children were more exposed to several contaminants. Exposure to chemical contaminant mixtures was not associated with overall basal ganglia volume; however, two organophosphate esters (2IPPDPP and 4IPPDPP) were both associated with a larger globus pallidus, a basal ganglia sub-region. Results highlight demographic disparities in exposure and suggest possible risks to a brain region key for healthy emotional development. • This is the first study of contaminant mixtures' impact on developing brain structure. • Analyses focused on the basal ganglia – a brain region vulnerable to exposure. • Children were exposed to all 6 classes of contaminants studied. • Non-White and lower-income children had higher chemical exposures. • 2IPPDPP and 4IPPDPP were associated with a larger globus pallidus within the basal ganglia. [ABSTRACT FROM AUTHOR]

The Indo-Pacific bottlenose dolphin (Tursiops aduncus), classified as a new species since 1998, is underexplored in ecotoxicology owing to ethical constraints and the lack of specific in vitro models. Herein, we established the first skin fibroblast cell line (TaSF) from an Indo-Pacific bottlenose dolphin stranded along the Pearl River Estuary, China. TaSF cells exhibited strong proliferation in early passages but ceased mitosis at passage 19, likely owing to reaching the Hayflick limit. Morphology and immunofluorescence tests confirmed the fibroblastic nature of these cells. Karyotyping revealed 21 pairs of autosomes and 1 pair of sex chromosomes (XY), consistent with many cetaceans. To facilitate long-term future studies, TaSF cells were immortalized with exogenous simian virus 40 T antigen, creating the TaSFT cell line. The cytotoxic effects of 27 contaminants, including 6 organotins (OTs), 10 per- and polyfluoroalkyl substances (PFASs), and 11 phthalates (PAEs), on TaSFT cells were evaluated after 24-h exposure. Among these chemicals, OTs exhibited the strongest cytotoxicity, and both OTs and PFASs showed structure-related toxicity. These findings confirm the feasibility of TaSFT cells as a novel tool for ecotoxicity research on the Indo-Pacific bottlenose dolphin and highlight the need for further investigation into the environmental contaminant pressures on this species. [Display omitted] • First dermal fibroblast cell line (TaSF) established from Tursiops aduncus. • TaSF cell karyotype and lifespan similar to other cetacean dermal cell lines. • SV40T antigen overexpression extended the lifespan of TaSFT cells. • OTs and PFASs exhibited structure-related cytotoxicity on TaSFT cells. • TaSFT is a novel tool for ecotoxicity research on Indo-Pacific bottlenose dolphins. [ABSTRACT FROM AUTHOR]

Ecologically unequal exchange arises if more developed economies (‘core’) shift the environmental burden of their consumption and capital accumulation to less developed economies (‘periphery’/‘semi-core’). Here we demonstrate that human populations in core regions can benefit from the use of products containing toxic chemicals while transferring to the periphery the risk of human and ecological exposure to emissions associated with manufacturing and waste disposal. We use a global scale substance flow analysis approach to quantify the emissions of polybrominated diphenyl ethers (PBDEs), a group of flame retardants added to consumer products, that are embodied in the trade of chemicals, products and wastes between seven world regions over the 2000–2020 time period. We find that core regions have off-loaded PBDE emissions, mostly associated with the disposal of electrical and electronic waste (e-waste), to semi-core and peripheral regions in mainland China and the Global South. In core regions this results in small emissions that mostly occur during the product use phase, whereas in peripheral regions emissions are much higher and dominated by end of life disposal. The transfer of toxic chemical emissions between core and periphery can be quantified and should be accounted for when appraising the costs and benefits of global trade relationships.

The paper presents the results of the research within the territory of the Khakas Republic of foods in terms of chemical safety indicators. The rate of non-oncogenic risk in relation to food consumption was determined as well as the analysis of alimentary-dependent diseases levels was carried out. A number of suggestions aimed at reducing dietary risk factors were made.

Wastewater from municipal, agricultural and industrial sources is a pervasive contaminant of aquatic environments worldwide. Most studies that have investigated the negative impacts of wastewater on organisms have taken place in a laboratory. Here, we tested whether fish behaviour is altered by exposure to environmentally relevant concentrations of wastewater effluent in the field. We caged bluegill sunfish (Lepomis macrochirus) for 28 days at two sites downstream (adjacent to and 870 m) from a wastewater treatment plant and at a reference site without wastewater inputs. We found that exposed fish had a dampened response to simulated predation compared to unexposed fish, suggesting that fish may be at greater risk of predation after exposure to wastewater effluent. Fish held at the different sites did not differ in activity and exploration. Our results suggest that predator avoidance may be impaired in fish exposed to wastewater effluent, which could have detrimental implications for aquatic communities. [ABSTRACT FROM AUTHOR]

Effective ventilation in general hospital wards is important for controlling the transmission of airborne infectious agents that may cause respiratory diseases. This study investigates the potential of protected occupied zone ventilation (POV) to reduce the risk of cross-infection in hospital isolation wards. Two life-size breathing thermal manikins were used to simulate an infected patient lying in a bed and a sitting, receiving health care worker. N2O was used as a tracer gas to simulate the droplet nuclei exhaled by patients. The contaminant exposure index ε e x p was used to assess the risk of cross-infection for different configurations of the supply velocity, the patient's lying position and the exhaust openings. The contaminant exposure index (ε e x p ) shows that the ventilation strategy is effective, but this is also highly dependent on the supply velocity and the location of the exhaust relative to the patient's breathing zone. The patient's posterior position does not affect the personal exposure of the receiving patient. Compared to traditional ventilation systems, the POV system can reduce the risk of cross-infection in hospital isolation rooms. The full potential of a POV system can be achieved in an isolation ward where movement between the infected and protected zones is restricted or prohibited. [ABSTRACT FROM AUTHOR]

Consumption of locally caught fish provides health benefits but can be a route of exposure to methylmercury and other persistent environmental contaminants. Previous studies found that Asian women of childbearing age (WCBA) in the Milwaukee area have high levels of exposure through fish consumption but limited awareness of fish advisories. We conducted a focus group project to understand the influence of culture, attitudes, and beliefs on the fish consumption habits of Chinese, Hmong, and Karen WCBA who reside in the Milwaukee area to develop culturally appropriate educational materials. A total of 19 women aged 18-50 years identifying as Chinese, Hmong, or Karen were recruited. Three focus groups were held, each consisting of 6-7 participants from one ethnicity. Focus group transcripts were thematically analyzed and coded based on the integrated behavioral model. Nutritional benefits and availability were the most common reasons to eat locally caught fish. All participants were aware of risks associated with eating fish, yet few knew ways to mitigate risk and maximize benefits. Participants expressed interest in receiving health messages from trusted sources and recommended that messaging target families rather than just individuals. Participants who were confident in their self-efficacy expressed a greater likelihood of following health message guidelines. Results suggest providing culturally appropriate educational materials in preferred languages to Asian communities via local community organizations may increase self-efficacy and adherence to fish advisories. Future projects will evaluate the effectiveness of self-affirmation messaging among Asian WCBA and assess changes in fish consumption based on message content., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Human subpopulations experience different exposure to persistent organic pollutants (POPs) because of differences in the structure of their food webs and the extent of environmental contamination. Here we quantify the time-variant exposure of different human populations around the world to one representative POP, namely the polychlorinated biphenyl (PCB) congener 153, based on a dynamic simulation of both global environmental fate (using the model BETR-Global) and human food chain bioaccumulation (using the model ACC-HUMAN). The approach identifies subpopulations whose diets include a carnivorous mammal as experiencing the world’s highest PCB-153 exposure, i.e. the very large biomagnification potential of their food web more than makes up for the remoteness of their living environment. However, for subpopulations that do not eat warm-blooded carnivores, the proximity to sources of PCBs is more important than food web structure and environmental conditions for differentiating their exposure to PCBs.

In the present study, Gammarus fossarum was used to investigate the bioaccumulation and toxic effects of aquatic pollutants in the real environmental conditions. The novelty of the study is the evaluation of soluble tissue metal concentrations in gammarids as indicators in early assessment of metal exposure. In the Sutla River, industrially/rurally/agriculturally influenced catchment in North-Western Croatia, physico-chemical water properties pointed to disturbed ecological status, which was reflected on population scale as more than 50 times lower gammarid density compared to the reference location, Črnomerec Stream. Significantly higher levels of soluble toxic metals (Al, As, Cd, Pb, Sb, Sn, Sr) were observed in gammarids from the Sutla River compared to the reference site and reflected the data on higher total dissolved metal levels in the river water at that site. The soluble metal estimates were supplemented with the common multibiomarker approach, which showed significant biological responses for decreased acetylcholinesterase activity and increased total soluble protein concentrations, confirming stressed environmental conditions for biota in the Sutla River. Biomarker of metal exposure, metallothionein, was not induced and therefore, toxic effect of metals was not confirmed on molecular level. Comparable between-site pattern of soluble toxic metals in gammarids and total dissolved metal levels in water suggests that prior to biomarker response and observed toxic impact, soluble metals in tissue might be used as early warning signs of metal impact in the aquatic environment and improve the assessment of water quality. [ABSTRACT FROM AUTHOR]

Tire wear particle (TWP)-derived compounds may be of high concern to consumers when released in the root zone of edible plants. We exposed lettuce plants to the TWP-derived compounds diphenylguanidine (DPG), hexamethoxymethylmelamine (HMMM), benzothiazole (BTZ), N -phenyl-N'-(1,3-dimethylbutyl)- p -phenylenediamine (6PPD), and its quinone transformation product (6PPD-q) at concentrations of 1 mg L -1 in hydroponic solutions over 14 days to analyze if they are taken up and metabolized by the plants. Assuming that TWP may be a long-term source of TWP-derived compounds to plants, we further investigated the effect of leaching from TWP on the concentration of leachate compounds in lettuce leaves by adding constantly leaching TWP to the hydroponic solutions. Concentrations in leaves, roots, and nutrient solution were quantified by triple quadrupole mass spectrometry, and metabolites in the leaves were identified by Orbitrap high resolution mass spectrometry. This study demonstrates that TWP-derived compounds are readily taken up by lettuce with measured maximum leaf concentrations between ∼0.75 (6PPD) and 20 μg g -1 (HMMM). Although these compounds were metabolized in the plant, we identified several transformation products, most of which proved to be more stable in the lettuce leaves than the parent compounds. Furthermore, continuous leaching from TWP led to a resupply and replenishment of the metabolized compounds in the lettuce leaves. The stability of metabolized TWP-derived compounds with largely unknown toxicities is particularly concerning and is an important new aspect for the impact assessment of TWP in the environment.

Contaminant exposure can vary between species but primary causes of it are often unclear. In order to estimate heavy metal intake of two sympatric passerines – Ficedula hypoleuca Pall. and Parus ater L. – we studied nestling diet and metal concentrations in prey invertebrates, near the Middle Ural copper smelter and in an unpolluted area. Diet of P. ater contained more Cu, Cd and Zn compared to F. hypoleuca and the same amount of Pb. Contribution of different prey taxa to bird metal intake was not equal to their dietary proportion. Proportion of Cu, Zn, Pb and Cd provided to birds by spiders and molluscs, as well as Cd and Pb provided by ants and imagoes Diptera, exceeded their dietary fraction by several times. In contrast, the contribution of Lepidoptera and sawfly larvae to bird metal intake was less than their dietary proportion. Pollution-related changes in the diet modified bird contaminant exposure along with pollutant concentrations in preys. [Copyright &y& Elsevier]

Abstract: Five human and five wildlife receptor-oriented exposure models were compared with the aim to identify similarities, differences and areas where both fields can learn from each other. Similarities were revealed in exposure endpoints, chemical stressors and extent of model validation. Differences were observed in effect endpoints, non-chemical stressors, exposure routes and media, and parameter uncertainty assessment. The most outstanding differences related to the simulation of behaviour and the representation of individuals and space. Whereas human models use static individuals and obtain activity patterns from databases, activity patterns for wildlife tend to be an emerging property of dynamic individuals, resulting from interactions with the surrounding environment. These differences can be explained by differences in legislation, dominant exposure routes and data availability. Wildlife models can serve as a source of inspiration for human models with respect to the simulation of emergent activity patterns and the inclusion of non-chemical stressors. Human models can act as a source of inspiration for wildlife models when it comes to including multiple exposure routes and the compilation and use of activity data. These adaptations could result in a more holistic approach, in line with current environmental policy that advances towards a more integrated health approach. [Copyright &y& Elsevier]

Abstract: Estuarine sediment contamination is a growing significant ecological issue in New Zealand. Methods of assessing toxicity and ecological impacts in a cost effective way are currently limited. Further to that is a need to develop bioassays that generate data quickly and cost effectively and have ecological relevance to the wider community. A chronic full life-cycle bioassay to assess the toxicity of New Zealand estuarine sediments using the marine harpacticoid copepod Robertsonia propinqua has been investigated. Sediment samples were collected from the Bay of Plenty region and included two polluted and one reference site. Sources of pollutants in the contaminated field sites originated from a variety of sources and generally include nutrients, pesticides and herbicides and the pollutants zinc, copper, lead and polycyclic aromatic hydrocarbons (PAHs). Conversely, the reference site was exposed to low levels of contaminants due to the relatively undeveloped catchment. Adult male and female copepods were exposed to field collected sediments for 24 days under flow-through conditions at 21°C and 12h L:D cycles. Five endpoints were recorded: male and female survival, fecundity (number of gravid females per replicate at the end of the test), clutch size per female, number of eggs per sample and juvenile survival (number of nauplii and copepodites per replicate at the end of the test). Adult mortality was observed in all sediment samples but the number of males, gravid females, clutch size per female and number of eggs produced were not affected by either the contaminated or reference sediment samples. However, the contaminated sediments did reduce reproductive output (i.e. nauplii and copepodite production). Therefore, we conclude that reproductive endpoints provide a good measure of sediment-associated contaminant effects compared with adult R. propinqua survivorship. It may be that a change in focus from chemical thresholds without ecological relevance or lethal dose threshold methods, to more subtle but ecologically significant elements of faunal life, such as reproductive success, are a more sensitive and a long term ecologically informative method. [Copyright &y& Elsevier]

Although several studies have suggested that behavioural measures may be more comprehensive than other biomarkers for indicating an organism’s health or welfare, this has rarely been investigated in free-living terrestrial vertebrates. Here we examine the expression of dawn singing behaviour in a free-living small songbird in relation to environmental pollution. We compared the singing behaviour of male great tits Parus major inhabiting an area extremely polluted with heavy metals with that of males inhabiting areas of low(er) pollution (at 4 and 20 km distance from the pollution source). Males at the most polluted site had a significantly smaller repertoire size than males at the two other sites. They also produced a significantly lower total amount of song during the dawn chorus than the males at a distance of 4 km from the pollution source. Our results, although non-experimental and obtained in field conditions, strongly suggest that heavy metal pollution might affect the expression of singing behaviour. Taking into account that previous studies were not able to detect clear, straightforward differences between the health of great tits at the most polluted site and at 4 km distance from the pollution source, our results suggest that the singing behaviour of great tits may be a useful indicator of environmental stress at the population level. [ABSTRACT FROM AUTHOR]

Although occupational exposure limits are sought. to establish health-based standards, they do not always give a sufficient basis for planning an indoor air climate that is good and comfortable for the occupants in industrial work rooms. This paper considers methodologies bywhich the desired level, i.e., target level, of air quality in industrial settings can be defined, taking into account feasibility issues. Risk assessment based on health criteria is compared with risk-assessment based on 'Best Available Technology' (BAT). Because health-based risk estimates at low concentration regions are rather inaccurate,the technology-based approach is emphasized. The technological approach is based on information on the prevailing concentrations in industrial work environments and the benchmark air quality attained with the best achievable technology. The prevailing contaminant concentrations are obtained from a contaminant exposure databank, and the benchmark air quality by field measurements in industrial work rooms equipped with advanced ventilation and production technology. As an example, the target level assessment has been applied to formaldehyde, totalinorganic dust and hexavalent chromium, which are common contaminants in work room air. [ABSTRACT FROM AUTHOR]

This study investigated the influence of medical equipment on contaminant levels in the sterile field of an operating room (OR) equipped with unidirectional downflow (UDF). Nitrous oxide (N 2 O) tracer gas was used to simulate constant emission both inside and outside the operating field. Medical equipment positioned above the sterile field consisted of two surgical lights and one fluoroscopy imaging device. This study compared the effect of different configurations of the equipment layout on the contaminant levels at several points in the proximity of a simulated patient. The air samples in the case without medical equipment had significantly lower (p < 0.01) N 2 O (ppm) levels than the rest of the cases with medical equipment when the pollution source was located inside the operating field. The normalized outdoor exhaust concentrations were substantially higher when the pollution source was positioned inside the operating field than when the pollution source was positioned outside the operating field. When the pollution source was located inside the operating field at a height of 1.5 m above the floor, the outdoor exhaust removal index was <1 when the sterile field was free of equipment. When obstructed by medical equipment, the unidirectional downflow (UDF) systems did not reduce the outdoor exhaust removal index compared to completely mixed conditions. The value of the outdoor exhaust removal index was lower than 1 regardless of the presence of medical equipment when the pollution source was located outside the operating field at the same height of 1.5 m above the floor. • The impact of equipment on contaminant levels in an operating room was investigated. • The operating room was equipped with unidirectional downflow (UDF). • Nitrous oxide was used to simulate emission of bioaerosols in the operating field. • Medical equipment consisted of two surgical lights and one fluoroscopy imaging device. • UDF systems obstructed by equipment do not reduce the contaminant removal index. [ABSTRACT FROM AUTHOR]

Fish consumption is associated with both health benefits from high-quality proteins, minerals, vitamins, and fatty acids and risks from contaminants in fish. Fish consumption advisories are issued by many government agencies to keep exposure to contaminants at a safe level. Such advisories are typically based on fillets and neglect consumption of other fish parts such as eggs by certain subpopulations. To evaluate potential for dietary exposure to toxic organic chemicals via fish eggs, we analyzed polybrominated diphenyl ethers (PBDEs), polychlorinated naphthalenes (PCNs), dioxin-like polychlorinated biphenyls (dlPCBs), and polychlorinated dibenzodioxins/furans (PCDD/Fs) in paired fillet and eggs of fish from a tributary to Lake Ontario, one of the North American Great Lakes. All wet weight based concentrations in fish eggs were statistically higher than in the paired fillet samples. In fish eggs, concentrations of Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 41-118, 0.3-1.7, and 30-128 ng/g wet weight (ww), respectively; Σ3PCDD/Fs and total (dlPCB+ PCDD/Fs) toxic equivalents (TEQs) were 4-22 and 9-54 pg/g ww, respectively. In fillet samples, Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 4-116, 0.05-0.66, and 6-85 ng/g, respectively; Σ3PCDD/Fs and TEQs were 2-10 and 3.4-31 pg/g ww, respectively. In contrast, the fillets had higher lipid normalized concentrations than the paired egg samples, suggesting that these chemicals did not reach equilibrium between the fillets and eggs. Accordingly, measured concentrations in eggs or empirical relationship with fillet rather than prediction from equilibrium partitioning model should be used to evaluate contaminant exposure via consumption of fish eggs. For fatty fish from the lower Great Lakes area, we suggest one fillet meal be reduced from the advised fish consumption frequency for consumptions of 207 ± 37, 39 ± 2, 105 ± 51, and 119 ± 9 g fish eggs of brown trout, Chinook salmon, Coho salmon, and rainbow trout, respectively.

Contaminant exposure is widespread among marine mammals but is of unknown significance. This study characterized organochlorine bioaccumulation in pilot whales, and these bioaccumulation patterns are proposed as representative of Northwest (NW) Atlantic cetacea. Samples werecollected from whales stranded in Massachusetts and caught in nets. Polychlorinated biphenyl (PCB) and chlorinated pesticide concentrations were determined via GC/ECD and found to be similar to those reported for other NW Atlantic odontocetes. The organochlorine in highest concentration was 4,4-DDE, followed by trans-nonachlor, 4,4-DDD, dieldrin, cis-chlordane, Cl4(52), Cl5(95), Cl5(101), Cl5(118), Cl6(138), Cl6(149), Cl6(153), Cl7(180), and Cl7(187). The concentration of 19 pesticides was higher in blubber (21 1 26 mug/g lipid 'ppm') than liver(5.0 1 7.1 ppm). The concentration of 26 PCB congeners was also greater in blubber (7.6 1 7.1 ppm) than liver (0.4 1 7.3 ppm). Principal component analysis and ANOVA indicated that blubber accumulated proportionately more of the most recalcitrant compounds, such as 4,4-DDE and nonmetabolizable PCBs, compared to liver. Whales that stranded together had more similar bioaccumulation than animals of the same gender or maturity. The high variation among individuals in tissue concentrations and the similarity within a stranding group suggest that pilot whale pods are exposed to a large range of pollutant sources, such as through different prey and feeding locations. [ABSTRACT FROM AUTHOR]