Analysis of phytoestrogens,progestogens and estrogens in environmental waters from Rio de Janeiro (Brazil)

The environment is currently exposed to a large variety of man-made chemicals (e.g. for industrial, medicinal use) which have potential adverse effects to its ecological status. In addition, the densely populated areas represent local high emissions of those chemicals leading to more aggravating consequences. Estrogenic compounds that end-up in environmental water directly affect living organisms by interfering with their endocrine metabolism. The assessment of their presence in the environment requires sensitive and selective analytical methods. Nineteen estrogenic compounds belonging to different classes (5 free estrogens, 6 conjugated estrogens, 3 progestogens and 5 phytoestrogens) have been studied. The analytical methodology developed is based on solid phase extraction followed by liquid chromatography tandem mass spectrometry and has been applied to study the occurrence of the above mentioned analytes in environmental waters from the state of Rio de Janeiro (Brazil). Due to insufficient infra-structure in this region, waste waters are released onto the environment without or with incomplete previous treatment. The results show that high levels of the phytoestrogens daidzein, coumestrol and genistein of up to 366 ng/L and progesterone of up to 47 ng/L could be found in river water. Estrogens and their conjugated derivatives were detected in the lower ng/L range up to 7 ng/L. The main estrogens estrone, estradiol and the synthetic ethinyl estradiol could not be detected. The developed method showed overall good performance with recoveries above 80% (with one exception), limits of detection ≤ 2 ng/L, good linearity and reproducibility.     

Distribution of PCB congeners in aquatic ecosystems: A case study

Polychlorinated biphenyls (PCB) congeners were determined in water samples, sediments, and animal species in the frame of a survey of the River Arrone (Central Italy, near Rome) after a major contamination episode. Animal species were selected on the basis of their living and feeding habits and evaluated as candidate bioindicators of PCB pollution in this lotic ecosystem. Total PCB concentrations in water were found to be low (ng/L level), and in sediments, ranged from about 10 to 200 μg/kg dry weight, depending on the distance from the contamination source. PCB patterns in sediments showed a prevalence of higher chlorinated congeners over time. Concentrations in macroinvertebrates (Calopteryx splendens and Anax imperator) ranged from 60 to 400 μg/kg dry weight, showing significantly different species to species patterns. PCB concentrations were almost parallel in sediments for different sampling stations, while differences in patterns among species can be explained in terms of bioaccumulation/excretion mechanisms. Freshwater shrimps (Palaemonetes antennarius) were not found close to the contamination source, as a consequence of their extreme sensitivity to chemicals, and showed a peculiar pattern (almost exclusively determined by congeners 153, 138, and 180) probably originating from biodegradation mechanisms. Fish samples (Rutilus erythrophthalmus) showed the highest concentrations, as a combination of feeding habit, lipid content, and, probably, less effective biodegradation/excretion pathways. Congener patterns closely match those of Aroclor 1260, which originates from the contamination source. This study confirms that congener physical and chemical parameters, different degradation rates, feeding habits, and mobility of the analysed aquatic organisms, metabolism, and excretion mechanisms, are to be considered to explain the distinctive PCB patterns of different samples.     

Assessment of Genotoxicity of Lignin Substances as Risk Factors for Aquatic Ecosystems

The genotoxicity of lignin substances (LSs) isolated from biologically purified wastewaters of the pulp and paper industry was studied in experiments on Baikal endemic mollusks and corn. Both toxicity and mutagenic activity of LSs were revealed, with their levels depending on the physicochemical characteristics of LSs, the test organism, and experimental conditions. These results provide evidence that LSs discharged into water bodies create a genetic hazard to their ecosystems.     

Perfluoroalkyl substances in human milk: A first survey in Italy

Due to their widespread diffusion, perfluoroalkyl substances (PFASs) have been frequently found in the environment and in several animal species. It has been demonstrated that they can easily reach also humans, mainly through diet. Being lactation a major route of elimination of these contaminants, their occurrence in human milk is of particular interest, especially considering that it generally represents the unique food source for newborns. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), the two most important compounds of this family, have been frequently found in human milk at variable concentrations, but still limited data are available. The present study, the first conducted in Italy capable to detect these pollutants at ultra-trace levels by UPLC-MS/MS, confirmed the role of lactation as a relevant source of exposure for breastfed children. The measured concentrations ranged between 15 and 288 ng/L for PFOS and between 24 and 241 ng/L for PFOA. Moreover, mean concentrations and frequencies of both analytes resulted higher in milk samples provided by primiparous women, suggesting that the risk of intake might be higher for first-borns. Finally, comparing these results with previous data, PFOS gradual decrease over time since year 2000 was confirmed.     

Occurrence and distribution of organochlorine pesticides - lindane, p,p'-DDT, and heptachlor epoxide - in surface water of China

Persistent organochlorine pesticides pollutants (OCPs) have been reported to occur at relatively high concentrations in some Chinese waters. In order to map the distribution of organochlorine pesticides in the surface water throughout China, samples were collected from over 600 sites in seven major river basins and three main internal rivers drainage areas during 2003 and 2004. The surface water samples were analyzed for the representative organochlorine pesticides contaminants including lindane (gamma-HCH), p,p'-DDT and heptachlor epoxide. In general, the most frequently detected compound was lindane, being detected in 83.9% of samples (mean=31.3 ng/l; range <0.17-860 ng/l), and the highest concentration was present in the Yellow River basin. p,p'-DDT was detected in 63.1% of the samples collected (mean=14.6 ng/l; range <0.14-368 ng/l) with the highest concentration present in the Huaihe River basin. Heptachlor epoxide was detected in only 9.3% of water samples (range <0.11-10 ng/l). Measured concentrations for the three compounds were low and rarely exceed the environment quality standard for surface water of China. Lindane was more frequently detected at much higher concentrations in the rivers of northern China compared with those of southern China. The sites with higher concentration of lindane and p,p'-DDT mainly occurred in the Yellow River and Huaihe River basins, so the results of this investigation indicate that the organochlorine pesticide contamination of Yellow River and Huaihe River basins should be of particular concern relative to the other basins. When compared with other regions of the world, it appears that the Chinese surface water is moderately polluted by lindane and p,p'-DDT.     

Pharmaceuticals and personal care products (PPCPs): A review on environmental contamination in China

Pharmaceuticals and personal care products (PPCPs) which contain diverse organic groups, such as antibiotics, hormones, antimicrobial agents, synthetic musks, etc., have raised significant concerns in recently years for their persistent input and potential threat to ecological environment and human health. China is a large country with high production and consumption of PPCPs for its economic development and population growth in recent years. This may result in PPCP contamination in different environmental media of China. This review summarizes the current contamination status of different environment media, including sewage, surface water, sludge, sediments, soil, and wild animals, in China by PPCPs. The human body burden and adverse effects derived from PPCPs are also evaluated. Based on this review, it has been concluded that more contamination information of aquatic environment and wildlife as well as human body burden of PPCPs in different areas of China is urgent. Studies about their environmental behavior and control technologies need to be conducted, and acute and chronic toxicities of different PPCP groups should be investigated for assessing their potential ecological and health risks.     

Occurrence,fate and ecological risk of five typical azole fungicides as therapeutic and personal care products in the environment: A review

Azole fungicides are widely used to treat fungal infection in human. After application, these chemicals may reach to the receiving environment via direct or indirect discharge of wastewaters, thus posing potential risks to non-target organisms. We aimed to review the occurrence, fate and toxicological effects of some representative household azole fungicides in the environment. Azole fungicides were widely detected in surface water and sediment of the aquatic environment due to their incomplete removal in wastewater treatment plants. These chemicals are found resistant to microbial degradation, but can undergo photolysis under UV irradiation. Due to different physiochemical properties, azole fungicides showed different environmental behaviors. The residues of azole fungicides could cause toxic effects on aquatic organisms such as algae and fish. The reported effects include regulation changes in expression of cytochrome P450-related genes and alteration in CYP450-regulated steroidogenesis causing endocrine disruption in fish. Further studies are essential to investigate the removal of azole fungicides by advanced treatment technologies, environmental fate such as natural photolysis, and toxic pathways in aquatic organisms.     

Concentration and characteristics of depleted uranium in biological and water samples collected in Bosnia and Herzegovina

During Balkan conflicts in 1994-1995, depleted uranium (DU) ordnance was employed and was left in the battlefield. Health concern is related to the risk arising from contamination of the environment with DU penetrators and dust. In order to evaluate the impact of DU on the environment and population in Bosnia and Herzegovina, radiological survey of DU in biological and water samples were carried out over the period 12-24 October 2002. The uranium isotopic concentrations in biological samples collected in Bosnia and Herzegovina, mainly lichens, mosses and barks, were found to be in the range of 0.27-35.7 Bq kg(-1) for (238)U, 0.24-16.8 Bq kg(-1) for (234)U, and 0.02-1.11 Bq kg(-1) for (235)U, showing uranium levels to be higher than in the samples collected at the control site. Moreover, the (236)U in some of the samples was detectable. The isotopic ratios of (234)U/(238)U showed DU to be detectable in many biological samples at most sites examined, but in very low levels. The presence of DU in the biological samples was as a result of DU contamination in air. The uranium concentrations in water samples collected in Bosnia and Herzegovina were found to be in the range of 0.27-16.2 m Bq l(-1) for (238)U, 0.41-15.6 m Bq l(-1) for (234)U and 0.012-0.695 m Bq l(-1) for (235)U, and two water samples were observed to be DU positive; these values are much lower than those in mineral water found in central Italy and below the WHO guideline for public drinking water. From radiotoxicological point of view, at this moment there is no significant radiological risk related to these investigated sites in terms of possible DU contamination of water and/or plants.     

Fate of Irgarol 1051, diuron and their main metabolites in two UK marine systems after restrictions in antifouling paints

Two major antifouling biocides used worldwide, Irgarol 1051 and diuron, and their degradation products in Shoreham Harbour and Brighton Marina, UK were studied during 2003-2004. The highest concentrations of Irgarol 1051 were 136 and 102 ng L(-1) in water and 40 and 49 ng g(-1) dry weight in sediments for Shoreham Harbour and Brighton Marina, respectively. As the degradation product of Irgarol 1051, M1 was also widespread, with the highest concentration of 59 ng L(-1) in water and 23 ng g(-1) in sediments in Shoreham Harbour, and 37 ng L(-1) in water and 5.6 ng g(-1) in sediments in Brighton Marina. The target compounds showed enhanced concentrations during the boating season (May-July), when boats were being re-painted (January-February), and where the density of pleasure crafts was high. Overall, the concentration of Irgarol 1051 decreased significantly from late 2000 to early 2004, indicating the effectiveness of controlling its concentrations in the marine environment following restricted use. Diuron was only detected in 14% of water samples, and mostly absent from sediment samples.     

Environmental 238U and 232Th concentration measurements in an area of high level natural background radiation at Palong, Johor, Malaysia

Concentrations of uranium-238 and thorium-232 in soil, water, grass, moss and oil-palm fruit samples collected from an area of high background radiation were determined using neutron activation analysis (NAA). U-238 concentration in soil ranged from 4.9 mg kg(-1) (58.8 Bq kg(-1)) to 40.4 mg kg(-1) (484.8 Bq kg(-1)), Th-232 concentration ranged from 14.9 mg kg(-1) (59.6 Bq kg(-1)) to 301.0 mg kg(-1) (1204 Bq kg(-1)). The concentration of U-238 in grass samples ranged from below the detection limit to 0.076 mg kg(-1) (912 mBq kg(-1)), and Th-232 ranged from 0.008 mg kg(-1) (32 mBq kg(-1)) to 0.343 mg kg(-1) (1.372 Bq kg(-1)). U-238 content in water samples ranged from 0.33 mg kg(-1) (4.0 Bq L(-1)) to 1.40 mg kg(-1) (16.8 Bq L(-1)), and Th-232 ranged from 0.19 mg kg(-1) (0.76 Bq L(-1)) to 0.66 mg kg(-1) (2.64 Bq L(-1)). It can be said that the concentrations of environmental U-238 and Th-232 in grass and water samples in the study area are insignificant. Mosses were found to be possible bio-radiological indicators due to their high absorption of the heavy radioelements from the environment.     

Perfluoroalkyl compounds in Danish wastewater treatment plants and aquatic environments

This study reports the results of a screening survey of perfluoroalkyl compounds (PFCs) in the Danish environment. The study included point sources (municipal and industrial wastewater treatment plants and landfill sites) and the marine and freshwater environments. Effluent and influent water and sewage sludge were analysed for point sources. Sediment, blue mussels (Mytilus edulis) and liver from plaice (Pleuronectes platessa), flounder (Platichthys flesus) and eel (Anguilla anguilla) were analysed for the freshwater and marine environments. The results obtained show a diffuse PFCs contamination of the Danish environment with concentrations similar to those measured in other countries with the absence of primary contamination sources such as fluorochemical production. PFOS and PFOA were generally the most dominating PFCs measured in both point sources and the aquatic environments. PFCs were found in both inflow and outflow water and sewage sludge from municipal and industrial wastewater treatment plants (WWTPs), indicating that WWTPs can be significant sources to PFCs in the environment. This is also reflected in the locally elevated PFCs concentrations found in fish like eels from shallow freshwater and marine areas. However, the highest PFCs concentrations found in fish in this study was in plaice from the Skagerrak (156 ng/g wet weight PFOS), but it is unknown if this can be related to significant sources in the North Sea region or to differences between species. The concentrations of PFCs were below the detection limit in all analysed freshwater and marine samples of sediment and mussels. Despite the relatively low PFCs concentrations measured in marine fish, the high bioaccumulation potential of PFCs, particularly PFOS, may lead to high concentrations of PFCs in marine mammals as shown by previous investigations.     

Assessment of groundwater contamination by nitrate leaching from intensive vegetable cultivation using geographical information system

This study employed the Geographical Information System (GIS) technology to investigate nitrate contamination of groundwater by agrochemical fertilizers in the Kakamigahara Heights, Gifu Prefecture, central Japan. Thematic information and chemical data of groundwater from the Heights were analyzed in a GIS environment to study the extent and variation of nitrate contamination and to establish spatial relationships with responsible land use types. The high and correlated concentrations of Ca(2+), Mg(2+), SO(4)(2-), and NO(3)(-) reflected the polluted nature of the unconfined highly permeable Kakamigahara aquifer. Ninety percent of the water samples showed nitrate concentrations above the human affected value (3 mg/l NO(3)(-)), while more than 30% have exceeded the maximum acceptable level (44 mg/l NO(3)(-)) according to Japan regulations. The spatial analyses indicated that groundwater contamination by nitrate is closely associated with one specific land use class, the "vegetable fields". The nitrate concentration of groundwater under vegetable fields was significantly higher than that under urban land or paddy fields. Most of the unacceptable nitrate levels were encountered in boreholes assigned to "vegetable fields" but a few were also found in boreholes allotted to "urban" class. Therefore, the vegetable fields were considered the principal source of nitrate contamination of groundwater in the Kakamigahara. However, contamination from urban sources is also possible.     

Cytogenetic monitoring of domestic mammals exposed to wastewaters from the localities of Dladla and Boukallou near Settat, Morocco

The aim of this work was to know the biological impact of wastewaters on livestock in the localities of Dladla and Boukallou (Town of Settat, Morocco), where wastewaters are largely used by the local population for their agricultural activities. We used the micronucleus (MN) test in cytochalasin B blocked binucleated cells (BNC) to assess the possible induced genetic effects. The cellular proliferation index (PI) was also calculated. Blood samples were collected from sheep, bovines and mules and peripheral blood cultures were made according to our laboratories' standard methodology. The results showed a significant increase of micronucleated cells in the lymphocytes of the exposed animals (14+/-8.79 MN/500 BNC) compared to the control (3+/-1.54 MN/500 BNC). The PI showed a nonsignificant decrease in the exposed animals. The highest MN frequency was found in mules which is probably due to their more sedentary life. Direct use of the wastewater by the animals as their source of drinking water significantly increased the frequency of cells with micronuclei. We also established an inverse correlation between the chromosome number and the PI. These results suggest a serious degradation of the ecosystem due to the wastewaters with a direct impact on its inhabitants.     

Natural and synthetic endocrine disrupting compounds (EDCs) in water, sediment and biota of a coastal lagoon

We report a survey on the occurrence and distribution of natural (17beta-estradiol, E2; estrone, E1) and synthetic (nonylphenol, NP; nonylphenol monoethoxylate carboxylate, NP1EC; bisphenol-A, BPA; benzophenone, BP; mestranol, MES; 17alpha-ethinylestradiol, EE2; diethylstilbestrol, DES) endocrine disrupting compounds (EDCs) in water, sediment and biota (Mediterranean mussel, Mytilus galloprovincialis) in the Venice lagoon, a highly urbanized coastal water ecosystem that receives both industrial and municipal wastewater effluents. The survey was preceded by the development of tailor made extraction and clean-up procedures for the simultaneous HPLC-ESI-MS determination of all examined EDCs in sediment and biota samples. Satisfactory extraction performances and method detection limits (MDLs) were obtained for almost all EDCs. Most of the selected compounds were found in water and sediment (concentration range: 2.8-211 ng/L, and 3.1-289 microg/kg, d.w., respectively), while only 17alpha-ethinylestradiol and nonylphenol were recorded in biota samples (conc. range: 7.2-240 ng/g, d.w.). 17beta-estradiol and ethinylestradiol contributed mostly to the water estradiol equivalent concentration (EEQ) (1.1-191 ng/L, average: 25 ng/L), while synthetic EDCs (17alpha-ethinylestradiol, diethylstilbestrol) were mainly responsible of the sediment EEQ (1.1-191 microg/kg, average: 71 microg/kg, d.w.). Whenever diethylstilbestrol was not recorded in the sediment, water EEQs were similar to sediment EEQs. A remarkable increase of nonylphenol was observed in sediments over the last decade.     

水样不同处理方式对高锰酸盐指数测定值的影响

研究了水样不同处理方式对三峡水库干流江段高锰酸盐指数（CODMn）测定值的影响。结果表明,悬浮颗粒物浓度（〖WTBX〗SS〖WTBZ〗）是澄清样和浑样之间、清样和浑样之间、清样和澄清样之间高锰酸盐指数差别的主要影响因子;用非线形回归方法得出了水样不同处理方式下高锰酸盐指数间的经验关系,并用实测数据进行了验证,结果表明,计算值和实测值吻合良好。依据〖WTBX〗SS〖WTBZ〗和所得经验关系,可计算高锰酸盐指数所表征有机物(CODMn)即OS(CODMn)）作为一个整体在水－固两相之间的分配,及其在粗颗粒物和细颗粒物上的赋存比例。河床上覆水体中溶解态、颗粒态OS(CODMn)所占比例皆随〖WTBX〗SS〖WTBZ〗而发生显著变化。〖WTBX〗SS〖WTBZ〗大于1 000 mg/L时,80％以上的OS(CODMn)赋存于悬浮颗粒物,澄清30 min能去除60％以上的OS(CODMn)。     

Levels and distribution of organochlorines in fish from Indonesia

Organochlorines such as PCBs, DDTs, HCHs, CHLs and HCB were determined in pooled whole body homogenized of fish samples collected from five locations during 1998 and 2003 in order to understand their contamination status, temporal and spatial variation in Indonesian waters. PCBs and DDTs were the predominant contaminants with concentrations from 9.7 to 2700 ng/g lipid wt. and 12 to 1100 ng/g lipid wt., respectively, while HCHs (nd-24 ng/g lipid wt.), CHL compounds (nd-81 ng/g lipid wt.) and HCB (0.22-28 ng/g lipid wt.) were one to two orders of magnitude lower. Among the locations, PCBs and CHLs were higher in the samples from highly industrialized and thickly populated-locations, whereas OC pesticides such as DDTs and HCHs were particularly more prominent in suburban and rural areas. Levels of OCs observed in the waters surrounding Java Island were higher than those in Sumatra Island, implying significant use of OCs in highly populated Java Island. Concentrations of PCBs and DDTs in fish from Jakarta Bay were significantly lower in the samples collected in 2003 as compared to fish in 1998, indicating decreasing trend of these compounds in the Indonesian environment. Recent estimated average daily intakes of PCBs (0.81 microg/person/day), DDTs (1.1 microg/person/day), HCHs (0.018 microg/person/day), CHLs (0.010 microg/person/day) were much lower than the threshold values recommended by various agencies, suggesting minimal risk of this compound via fish ingestion to Indonesians.     

Carcinogenic potential, levels and sources of polycyclic aromatic hydrocarbon mixtures in indoor and outdoor environments and their implications for air quality standards

Both the World Health Organization and the UK Expert Panel on Air Quality Standards (EPAQS) have considered benzo(a)pyrene (BaP) as a marker of the carcinogenic potency of the polycyclic aromatic hydrocarbons (PAH) mixture, when recommending their respective guidelines for PAHs in outdoor air. The aim of this research is to compare the concentrations and relative abundance of individual PAH and their contribution to the overall carcinogenic potential of the PAH mixture in indoor and outdoor environments to assess the suitability of the UK air quality standard derived for outdoor air for use as a guideline for indoor environments. Samples were collected onto filters using active sampling in different indoor and outdoor microenvironments. The ratio of individual compounds to BaP, the BaP equivalent concentrations and the percentage contribution of each individual compound to the total carcinogenic potential of the PAH mixture were calculated. Mean concentrations were generally lower indoors (BaP=0.10 ng/m(3)) than outdoors (BaP=0.19 ng/m(3)), with the exception of indoor environments with wood burners (BaP=2.4 ng/m(3)) or ETS (BaP=0.6 ng/m(3)). The ratio of individual PAHs to BaP showed no significant differences between indoors (e.g. DahA/BaP=0.27) and outdoors (DahA/BaP=0.31). The relative contribution of BaP to the PAH overall carcinogenic potency is similar indoors (49%), outdoors (54%) and in the smelter environment (48%) used by EPAQS to derive the UK Air Quality Standard for ambient air. These results suggest the suitability of BaP as a marker for the carcinogenic potential of the PAH mixture irrespective of the environment. Despite small differences in PAH mixture composition indoors and outdoors, the level of protection afforded by the present EPAQS standard is likely to be similar whether it is applied to indoor or outdoor air.     

江苏天目湖表层沉积物中多环芳烃污染特征与来源

区别于长江三角洲地区众多的大型天然浅水湖泊，江苏天目湖是一个较深的水库型湖泊，也是重要的城乡生活及工农业水源地之一。为了解天目湖表层沉积物中多环芳烃（PAHs）污染状况， 2006年在天目湖全湖采集7个点位的表层沉积物样品，利用GC/MS分析了16种优控PAHs。结果表明：天目湖表层沉积物中16种优控PAHs总量介于28750~71393 ng/g（干重），平均值为45852 ng/g；在空间分布上，北部受污染程度高于南部，主要是北部旅游业快速发展导致污染物排放的影响；沉积物中总有机碳含量与PAHs总量呈显著相关；利用特征化合物指数对PAHs的来源进行判别，指示天目湖表层沉积物中PAHs的主要来源是木材、煤的不完全燃烧。与不同地区水体沉积物PAHs含量对比表明，天目湖PAHs污染处于一个低至中等程度。基于沉积物中多环芳烃的环境质量标准，仅有1个样点芴浓度超过风险效应低值，但远小于毒性风险效应中值，因此沉积物中多环芳烃的生态风险较小。然而天目湖表层沉积物中的PAHs的污染程度已超过南水北调东线所经过的南四湖，而且天目湖湖水较深，湖水交换周期比较长，其PAHs污染应引起重视，需制定切实措施保护江苏“最后一泓净水”。     

Antibiotics in the aquatic environments: A review of the European scenario

The discovery of antibiotics is considered one of the most significant scientific achievements of the 20th century, revolutionizing both human and veterinary medicine. However, antibiotics have been recently recognized as an emerging class of environmental contaminants since they have been massively administrated in humans and animals and persist in the environment through a complex vicious cycle of transformation and bioaccumulation. The diffusion of antibiotics in the environment, particularly in natural water systems, contributes to the development and global dissemination of antibiotic resistance. This phenomenon is one of the most important challenges to the health care sector in the 21st century. As a result, studies on the occurrence, fate, and effects of antibiotics in European aqueous environments have increased in the last years. Nevertheless, their potential aquatic ecotoxicity and human toxicity via environmental exposure routes remain unknown. Consequently, antibiotics are not regulated through the current European environmental water quality standards, which requires evidence concerning their widespread environmental contamination and intrinsic hazard. In this context, this literature review summarizes the state of knowledge on the occurrence of antibiotics in the different aqueous environmental systems across the Europe, as reported since 2000. Relating this subject to antibiotic consumption and their dynamic behavior in the environment, the acquired insights provide an improved understanding on aquatic pollution by antibiotics to outline the European scenario. Moreover, it addresses challenges, prospects for future research, and typical topics to stimulate discussion.     

The precautionary principle and chemicals management: The example of perfluoroalkyl acids in groundwater

Already in the late 1990s microgram-per-liter levels of perfluorooctane sulfonate (PFOS) were measured in water samples from areas where fire-fighting foams were used or spilled. Despite these early warnings, the problems of groundwater, and thus drinking water, contaminated with perfluoroalkyl and polyfluoroalkyl substances (PFASs) including PFOS are only beginning to be addressed. It is clear that this PFAS contamination is poorly reversible and that the societal costs of clean-up will be high. This inability to reverse exposure in a reasonable timeframe is a major motivation for application of the precautionary principle in chemicals management. We conclude that exposure can be poorly reversible; 1) due to slow elimination kinetics in organisms, or 2) due to poorly reversible environmental contamination that leads to continuous exposure. In the second case, which is relevant for contaminated groundwater, the reversibility of exposure is not related to the magnitude of a chemical's bioaccumulation potential. We argue therefore that all PFASs entering groundwater, irrespective of their perfluoroalkyl chain length and bioaccumulation potential, will result in poorly reversible exposures and risks as well as further clean-up costs for society. To protect groundwater resources for future generations, society should consider a precautionary approach to chemicals management and prevent the use and release of highly persistent and mobile chemicals such as PFASs.