Screening-level Risk Assessment Research Articles

A GIS-based tool for bioaccumulation risk analysis and its application to study polychlorinated biphenyls in the Great Lakes

This paper presents a GIS-based tool named Arc-BEST (Bioaccumulation Evaluation Screening Tool) to perform spatially distributed bioaccumulation risk analyses. Estimating bioaccumulation risk is important to help predict potentially adverse effects from contaminants on ecosystems and human health, which are key factors in the development of sound public policy. Arc-BEST is based on the BEST model in the U.S. Army Corps of Engineers BRAMS (Bioaccumulation Risk Assessment Modeling System) software, released in 2012. It predicts concentration of concern contaminants in predators’ tissues from concentrations in organisms at the bottom of the food chain, and corresponding bioaccumulation factors. Additionally, it estimates carcinogenic and non-carcinogenic risks for humans that consume those species. The greatest contribution of Arc-BEST is that it enables the automated use of digital spatial data sets, which improves model creation speed, analysis and visualization of results, and comparison and cross-referencing with other geographic datasets. Furthermore, the model was improved to consider up to four trophic levels. The code is written in Python and is open-source. In this work Arc-BEST is used as part of a screening-level risk assessment process in order to identify hot spots where further studies and monitoring should be performed to ensure humans and ecosystems health. The tool is successfully applied to a case study in the Laurentian Great Lakes, where long-term effects of polychlorinated biphenyls (PCBs) is performed, based on measured concentrations in zebra mussels (Dreissena polymorpha), and local bioaccumulation factors from previous studies. Zebra mussels have a great filtration capacity and high bioconcentration rates, increasing the bioavailability of contaminants for predator species. PCBs concentrations in different-level predators are predicted. Furthermore, health risks for humans that consume sport fish are estimated for various exposure scenarios. The distribution of the risks in the lakes is analyzed, and critical areas are identified.

A refined ecological risk assessment for California red-legged frog, Delta smelt, and California tiger salamander exposed to malathion.

The California red-legged frog (CRLF), Delta smelt (DS), and California tiger salamander (CTS) are 3 species listed under the United States Federal Endangered Species Act (ESA), all of which inhabit aquatic ecosystems in California. The US Environmental Protection Agency (USEPA) has conducted deterministic screening-level risk assessments for these species potentially exposed to malathion, an organophosphorus insecticide and acaricide. Results from our screening-level analyses identified potential risk of direct effects to DS as well as indirect effects to all 3 species via reduction in prey. Accordingly, for those species and scenarios in which risk was identified at the screening level, we conducted a refined probabilistic risk assessment for CRLF, DS, and CTS. The refined ecological risk assessment (ERA) was conducted using best available data and approaches, as recommended by the 2013 National Research Council (NRC) report "Assessing Risks to Endangered and Threatened Species from Pesticides." Refined aquatic exposure models including the Pesticide Root Zone Model (PRZM), the Vegetative Filter Strip Modeling System (VFSMOD), the Variable Volume Water Model (VVWM), the Exposure Analysis Modeling System (EXAMS), and the Soil and Water Assessment Tool (SWAT) were used to generate estimated exposure concentrations (EECs) for malathion based on worst-case scenarios in California. Refined effects analyses involved developing concentration-response curves for fish and species sensitivity distributions (SSDs) for fish and aquatic invertebrates. Quantitative risk curves, field and mesocosm studies, surface-water monitoring data, and incident reports were considered in a weight-of-evidence approach. Currently, labeled uses of malathion are not expected to result in direct effects to CRLF, DS or CTS, or indirect effects due to effects on fish and invertebrate prey. Integr Environ Assess Manag 2018;14:224-239. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Study of pharmaceuticals in surface and wastewater from Cuernavaca, Morelos, Mexico: Occurrence and environmental risk assessment

The present work describes the first known study to date on the occurrence of pharmaceuticals in surface water and wastewater of Cuernavaca, the capital of the state of Morelos (México). Selected pharmaceuticals (a total of 35) were extracted from the collected water samples with a generic solid phase extraction (SPE) protocol and determined in the sample extracts by means of high-performance liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS). A screening level risk assessment combining the measured environmental concentrations (MECs) with dose-response data based on predicted no-effect concentrations (PNECs) was also applied to estimate Hazard Quotients (HQs) for the pharmaceuticals detected in the investigated area. A total of twelve pharmaceuticals were found in the water samples analyzed, with detection frequencies above 78% and in most cases of 100%. Overall, the most abundant pharmaceuticals in surface water were the analgesic and anti-inflammatory drugs naproxen (732–4880ng/L), acetaminophen (354–4460ng/L), and diclofenac (258–1398ng/L), and the lipid regulator bezafibrate (286–2100ng/L). On the contrary, other compounds like the β-blocker atenolol and the psychiatric drug carbamazepine were found at only a few ng or tens of ng per liter in the Apatlaco River. Despite the fact that some of the most abundant compounds showed good removal (>97%) during wastewater treatment, concentrations downstream the WWTP were only slightly lower than upstream. This indicates the existence of additional inputs of untreated wastewater into the river. Based on the obtained HQ-values, the concentrations of ibuprofen, sulfamethoxazole, diclofenac and naproxen present in the river could pose a high toxicity risk for the aquatic ecosystem. These findings highlight these pharmaceuticals as relevant organic contaminants in the area of study and the need to further monitor them in order to adopt appropriate measures to safeguard the ecosystem, and eventually human health.

Derivation of Occupational Thresholds of Toxicological Concern for Systemically Acting Noncarcinogenic Organic Chemicals.

Many substances in workplace do not have occupational exposure limits. The threshold of toxicological concern (TTC) principle is part of the hierarchy of approaches useful in occupational health risk assessment. The aim of this study was to derive occupational TTCs (OTTCs) reflecting the airborne concentrations below which no significant risk to workers would be anticipated. A reference dataset consisting of the 8-h threshold limit values-Time-Weighted Average for 280 organic substances was compiled. Each substance was classified into low (class I), intermediate (class II), or high (class III) hazard categories as per Cramer rules. For each chemical, n-octanol:water partition coefficient and vapor pressure along with the molecular weight were used to predict the blood:air partition coefficient. The blood:air partition coefficient along with data on water solubility and ventilation rate allowed the prediction of pulmonary retention factor and absorbed dose in workers. For each Cramer class, the distribution of the predicted doses was analyzed to identify the various percentile values corresponding to the OTTC. Accordingly, for Cramer classes I-III, the OTTCs derived in this study correspond to 0.15, 0.0085, and 0.006 mmol/d, respectively, at the 10th percentile level, while these values were 1.5, 0.09 and 0.03 mmol/d at the 25th percentile level. The proposed OTTCs are not meant to replace the traditional occupational exposure limits, but can be used in data-poor situations along with exposure estimates to support screening level risk assessment and prioritization.

Chemical monitoring of Swedish coastal waters indicates common exceedances of environmental thresholds, both for individual substances as well as their mixtures

Chemical pollution was monitored and assessed along the Swedish west coast. 62 of 172 analyzed organic chemicals were detected in the water phase of at least one of five monitored sites. A Concentration Addition based screening-level risk assessment indicates that all sites are put at risk from chemical contamination, with total risk quotients between 2 and 9. Only at one site did none of the individual chemicals exceeded its corresponding environmental threshold (PNEC, EQS). The monitoring data thus demonstrate a widespread blanket of diffuse pollution, with no clear trends among sites. Further issues critical for the environmental chemical risk assessment include the challenges to achieve sufficiently low levels of detection, especially for hormones and cypermethrin (a pyrethroid insecticide), the appropriate consideration of non-detects and the limited availability of reliable PNECs and EQS values.

Screening-level risk assessment applied to dredging of polluted sediments from Guanabara Bay, Rio de Janeiro, Brazil

Guanabara Bay is characterized by predominant eutrophication and anoxic sediments with a mixture of pollutants. The risk prognosis associated with the dumping of its dredged sediments into the open ocean was addressed by our algorithm. Our algorithm could prioritize areas, characterize major processes related to dredging, measure the potential risk of sediments, and predict the effects of sediment mixing. The estimated risk of dredged sediment was >10-fold than that of ocean sediments. Among metals, mercury represented 50–90% of the total risk. The transfer of dredged material into the ocean or internal dumping in the bay requires a 1:10 dilution to mitigate the risk and bring the risk levels close to that in the EPA criteria, below which there is less likelihood of adverse effects to the biota, and a 1:100 dilution to maintain the original characteristics of the ocean disposal control area. Our algorithm indicator can be used in the design of both aquatic and continental disposal of dredged materials and their management.

Occurrence and ecological risk assessment of emerging organic chemicals in urban rivers: Guangzhou as a case study in China

Urban rivers may receive contamination from various sources including point sources like domestic sewage and nonpoint sources (e.g., runoff), resulting in contamination with various chemicals. This study investigated the occurrence of emerging organic contaminants (3 endocrine disrupting compounds (EDCs), and 17 pharmaceuticals and personal care products (PPCPs)) in six urban rivers of a representative subtropical city, Guangzhou (southern China). Our results showed that EDCs and personal care products were frequently detected in the water phase and sediment phase. 4-nonylphenol (4-NP) was the most predominant compound with the highest concentration of 5050ng/L in the water phase and 14,400ng/g dry weight (dw) in the sediment. Generally, higher total concentrations of EDCs and PPCPs were detected in the four urban streams compared to the main stream Zhujiang River and the Liuxi River at the suburb area. A screening-level risk assessment showed that 4-nonylphenol and triclosan (TCS) pose potential risks to aquatic organisms in most sampling sites. For individual taxa, 4-NP may pose risks to various groups of aquatic organisms, while TCS only might pose high risks to algae. CapsuleHigher contamination of EDCs and PPCPs was observed in rivers in urban area; 4-nonylphenol and triclosan showed RQs>1 in >70% of the reported area.

Improving risk assessment of color additives in medical device polymers.

Many polymeric medical device materials contain color additives which could lead to adverse health effects. The potential health risk of color additives may be assessed by comparing the amount of color additive released over time to levels deemed to be safe based on available toxicity data. We propose a conservative model for exposure that requires only the diffusion coefficient of the additive in the polymer matrix, D, to be specified. The model is applied here using a model polymer (poly(ether-block-amide), PEBAX 2533) and color additive (quinizarin blue) system. Sorption experiments performed in an aqueous dispersion of quinizarin blue (QB) into neat PEBAX yielded a diffusivity D = 4.8 × 10-10 cm2 s-1 , and solubility S = 0.32 wt %. On the basis of these measurements, we validated the model by comparing predictions to the leaching profile of QB from a PEBAX matrix into physiologically representative media. Toxicity data are not available to estimate a safe level of exposure to QB, as a result, we used a Threshold of Toxicological Concern (TTC) value for QB of 90 µg/adult/day. Because only 30% of the QB is released in the first day of leaching for our film thickness and calculated D, we demonstrate that a device may contain significantly more color additive than the TTC value without giving rise to a toxicological concern. The findings suggest that an initial screening-level risk assessment of color additives and other potentially toxic compounds found in device polymers can be improved. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 310-319, 2018.

Conceptual Framework To Extend Life Cycle Assessment Using Near-Field Human Exposure Modeling and High-Throughput Tools for Chemicals.

Life Cycle Assessment (LCA) is a decision-making tool that accounts for multiple impacts across the life cycle of a product or service. This paper presents a conceptual framework to integrate human health impact assessment with risk screening approaches to extend LCA to include near-field chemical sources (e.g., those originating from consumer products and building materials) that have traditionally been excluded from LCA. A new generation of rapid human exposure modeling and high-throughput toxicity testing is transforming chemical risk prioritization and provides an opportunity for integration of screening-level risk assessment (RA) with LCA. The combined LCA and RA approach considers environmental impacts of products alongside risks to human health, which is consistent with regulatory frameworks addressing RA within a sustainability mindset. A case study is presented to juxtapose LCA and risk screening approaches for a chemical used in a consumer product. The case study demonstrates how these new risk screening tools can be used to inform toxicity impact estimates in LCA and highlights needs for future research. The framework provides a basis for developing tools and methods to support decision making on the use of chemicals in products.

ISTREEM(®) : An approach for broad-scale in-stream exposure assessment of "down-the-drain" chemicals.

The "in-stream exposure model" iSTREEM(®) , a Web-based model made freely available to the public by the American Cleaning Institute, provides a means to estimate concentrations of "down-the-drain" chemicals in effluent, receiving waters, and drinking water intakes across national and regional scales under mean annual and low-flow conditions. We provide an overview of the evolution and utility of the iSTREEM model as a screening-level risk assessment tool relevant for down-the-drain products. The spatial nature of the model, integrating point locations of facilities along a hydrologic network, provides a powerful framework to assess environmental exposure and risk in a spatial context. A case study compared national distributions of modeled concentrations of the fragrance 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8,-hexamethylcyclopenta-γ-2-benzopyran (HHCB) and the insect repellent N,N-Diethyl-m-toluamide (DEET) to available monitoring data at comparable flow conditions. The iSTREEM low-flow model results yielded a conservative distribution of values, whereas the mean-flow model results more closely resembled the concentration distribution of monitoring data. We demonstrate how model results can be used to construct a conservative estimation of the distribution of chemical concentrations for effluents and streams leading to the derivation of a predicted environmental concentration (PEC) using the high end of the concentration distribution (e.g., 90th percentile). Data requirements, assumptions, and applications of iSTREEM are discussed in the context of other down-the-drain modeling approaches to enhance understanding of comparative advantages and uncertainties for prospective users interested in exposure modeling for ecological risk assessment. Integr Environ Assess Manag 2016;12:782-792. © 2016 SETAC.

중금속 오염 준설토의 토양으로서의 유효활용을 위한 선별수준 생태위해도평가

중금속 오염 준설토의 토양으로서의 유효활용을 위한 선별수준 생태위해도평가

Risks associated with arsenic exposure resulting from the consumption of California wines sold in the United States

Concerns have recently been raised about the presence of arsenic (As) in wine. In this analysis, 101 different California wines were evaluated for organic and inorganic As concentration. The average concentrations of total inorganic As in red, blush and white wines were 6.12μg/L (range: 0.40–20.5μg/L), 21.6μg/L (range: 0.92–41.2μg/L) and 9.5μg/L (0.57–30.4μg/L). The average concentrations of total organic As in red, blush and white wines were 0.64μg/L (0.10–2.74μg/L), 0.99μg/L (0.50–2.28μg/L), and 0.51μg/L (0.10–1.78μg/L). A screening level risk assessment was conducted to assess the potential non-carcinogenic risk resulting from wine consumption. The hazard quotient (HQ) for the inorganic As RfD and the As content of red, blush and white wines was each less than one; indicating that the non-cancer health risk was insignificant. Results indicate that ingestion of California wine does not pose a hazard due to inorganic As content.

Using ToxCast to Explore Chemical Activities and Hazard Traits: A Case Study With Ortho-Phthalates.

US EPA's Toxicity Forecaster (ToxCastTM) is a tool with potential use in evaluating safer consumer products, conducting chemical alternatives analyses, prioritizing chemicals for exposure monitoring, and ultimately performing screening-level risk assessments. As a case study exploring a potential use of ToxCast, we evaluated ToxCast results for ortho-phthalates focused on the well-established toxicological endpoints of some members of this class. We compared molecular perturbations measured in ToxCast assays with the known apical toxicity endpoints of o-phthalates reported in the open literature to broadly reflect on the predictive capability of the high-throughput screening (HTS) assays. We grouped the ToxCast assays into defined sets to examine o-phthalate activity and potency. This study revealed several links between key molecular events assayed in vitro and chemical-specific hazard traits. In general, parent o-phthalates are more active than their monoester metabolites. The medium-chain length o-phthalate group is also more active than other o-phthalate groups, as supported by Toxicological Priority Index ranking and statistical methods. Some HTS assay results correlated with in vivo findings, but others did not. For example, there was a notable lack of assay activity to explain the known male reproductive toxicity of these compounds. Ultimately, HTS data resources such as ToxCast may inform us of sensitive upstream toxicity endpoints and may assist in the rapid identification of environmental chemical hazards for screening and prioritization. However, this case study shows that the absence of positive results in ToxCast in vitro assays cannot be interpreted as absence of related in vivo toxicity, and limited biological coverage by the assays remains a concern.

The US Army Corps of Engineers Scalable Approach to Estimating Loss of Life from Flooding

Although flooding can lead to many types of severe consequences, the primary objective of the US Army Corps of Engineers (USACE) dam and levee safety programs are to manage risk to the public who rely on those structures to keep them reasonably safe from flooding. Thus, reducing the risk associated with loss of life is paramount. USACE employs a scalable approach to estimating loss of life, where the goal is to invest an appropriate amount of resources to answer the question at hand. Given the large number of dams and levees within the USACE portfolio (over 700 dams and 15,000 miles of levees), a “one size fits all” approach does not work. Screening level risk assessments are carried out to initially characterize risk. That initial risk characterization informs prioritization of additional efforts such as interim risk management activities and more detailed risk assessments. More detailed risk assessments inform investment in long-term risk reduction measures, which include analysis and selection of major modification activities and implementation of non-structural measures including emergency management and evacuation planning. This paper describes the USACE scalable approach for estimating loss of life from flood events.

Car indoor air pollution by volatile organic compounds and aldehydes in Japan

Fifty-five organic substances including volatile organic compounds (VOCs) and aldehydes present in indoor air were measured from 24 car cabins in Japan. A screening-level risk assessment was also performed. Acetaldehyde (3.81–36.0 μg/m3), formaldehyde (3.26–26.7 μg/m3), n-tetradecane (below the method quantification limit (<MQL) to 47.7 μg/m3), toluene (4.23–78.3 μg/m3), and n-undecane (<MQL to 6.24 μg/m3) concentrations exceeded method detection limits in all the investigated car cabins. Ratios between indoor and outdoor concentrations revealed that most organic compounds originated from the car interior materials. Total volatile organic compound (TVOC) concentrations in 14 car cabins (58% of all car cabins) exceeded the advisable values established by the Ministry of Health, Labour and Welfare of Japan (400 μg/m3). The highest TVOC concentration (1136 μg/m3) was found in a new car (only one month since its purchase date). Nevertheless, TVOC concentrations exceeded the advisable value even for cars purchased over 10 years ago. Hazard quotients (HQs) for formaldehyde obtained using measured median and highest concentrations in both exposure scenarios for occupational use (residential time in a car cabin was assumed to be 8 h) were higher than that expected, a threshold indicative of potential adverse effects. Under the same exposure scenarios, HQ values for all other organic compounds remained below this threshold.

It is time to develop ecological thresholds of toxicological concern to assist environmental hazard assessment.

The threshold of toxicological concern (TTC) concept is well established for assessing human safety of food-contact substances and has been reapplied for a variety of endpoints, including carcinogenicity, teratogenicity, and reproductive toxicity. The TTC establishes an exposure level for chemicals below which no appreciable risk to human health or the environment is expected, based on a de minimis value for toxicity identified for many chemicals. Threshold of toxicological concern approaches have benefits for screening-level risk assessments, including the potential for rapid decision-making, fully utilizing existing knowledge, reasonable conservativeness for chemicals used in lower volumes (low production volume chemicals (e.g., < 1 t/yr), and reduction or elimination of unnecessary animal tests. Higher production volume chemicals (>1 t/yr) would in principle always require specific information because of the presumed higher exposure potential. The TTC approach has found particular favor in the assessment of chemicals used in cosmetics and personal care products, as well as other chemicals traditionally used in low volumes. Use of the TTC in environmental safety is just beginning, and initial attempts are being published. Key questions focus on hazard extrapolation of diverse taxa across trophic levels, importance of mode of action, and whether safe concentrations for ecosystems estimated from acute or chronic toxicity data are equally useful and in what contexts. The present study provides an overview of the theoretical basis for developing an ecological (eco)-TTC, with an initial exploration of chemical assessment and boundary conditions for use. An international collaboration under the International Life Sciences Institute Health and Environmental Sciences Institute has been established to address challenges related to developing and applying useful eco-TTC concepts.

Evaluation of a new screening-level risk assessment tool applied to non-indigenous marine invertebrates in Canadian coastal waters

Screening-level risk assessment tools for non-indigenous species are useful to inform management and policy decisions. While a number of tools have been developed to evaluate the risk of introductions in terrestrial and freshwater environments, only one tool is available for marine invertebrates [Marine Invertebrate Invasiveness Scoring Kit (MI-ISK)] and it has not been calibrated or evaluated previously. This paper introduces the Canadian Marine Invasive Screening Tool (CMIST), a tool based on a series of questions related to the sequence of events in the invasion process. We assessed the performance of both CMIST and MI-ISK using 60 species/ecosystem combinations of non-indigenous marine invertebrate species known to have been introduced to three Canadian marine ecoregions. Assessment scores were compared to the results of an expert opinion survey about the level of ecological risk posed by these species in these ecoregions. In addition, a simple way to quantify uncertainty and compute confidence limits surrounding expert evaluations and CMIST scores is presented; the technique could be incorporated into other existing tools. The risk scores returned by the two tools generally were similar, had comparable levels of inter-assessor variability, and correlated well with the results of the expert opinion survey for two of the three ecoregions. In the third ecoregion, we believe the lack of highly problematic species and greater uncertainty (linked to less reliable information) contributed to the weaker correlation. For all ecoregions, CMIST scores were more strongly correlated with expert opinion scores when compared to MI-ISK scores. Finally, we demonstrate how CMIST can be used for new incursions; for each ecoregion we scored 15 additional species not yet introduced and compared these scores with those of species already present. Overall CMIST is a promising screening-level tool; it distinguishes between elements of invasion risk (likelihood and impact), has fewer questions to score than similar tools, and could easily be adapted for other taxa.

Risk assessment of persistent pharmaceuticals in biosolids: Dealing with uncertainty

A screening-level risk assessment of biosolids-borne PPCPs in agricultural scenarios was developed in this work. While several of these compounds are efficiently removed in sewage treatment plants (STPs), others are recalcitrant to degradation and can be found in sludge at significant levels. As the rate of biosolids reuse for fertilising and/or amendment purposes is increasing, it is necessary to evaluate the fate in soil and possible biotransfer of this type of pollutants in the long-term. The study includes six compounds that were selected considering data availability, presence in sludge and persistence. Due to the scarce data still present in literature, a probabilistic assessment to address uncertainty was developed. A 95th percentile of the hazard index (HI) exceeding 1 was obtained, with main contributions of triclosan and carbamazepine. Although these estimates were obtained under a worst-case approach, and that they can vary depending on scenario characteristics, they change the least-concern classification associated to the presence of PPCPs in biosolids. A sensitivity analysis indicates the high influence of application rate and sludge concentration level on the results. Thus, the importance of developing new strategies of removal in advanced STPs and the establishment of a specific biosolids reuse regulation including this type of compounds acquires an added significance.

Pharmaceuticals and iodinated contrast media in a hospital wastewater: A case study to analyse their presence and characterise their environmental risk and hazard

This work analyses the presence of twenty-five pharmaceutical compounds belonging to seven different therapeutic groups and one iodinated contrast media (ICM) in a Spanish medium-size hospital located in the Valencia Region. Analysis of the target compounds in the hospital wastewater was performed by means of solid phase extraction (SPE) followed by liquid chromatography-tandem mass spectrometry analysis (HPLC-MS/MS). A screening level risk assessment combining the measured environmental concentrations (MECs) with dose-response data based on Predicted No Effect Concentration (PNEC) was also applied to estimate Hazard Quotients (HQs) for the compounds investigated. Additionally, the environmental hazard associated to the various compounds measured was assessed through the calculation of the Persistence, Bioaccumulation and Toxicity (PBT) Index, which categorizes compounds according to their environmentally damaging characteristics. The results of the study showed the presence of twenty-four out of the twenty-six compounds analysed at individual concentrations ranging from 5ngL−1 to 2mgL−1. The highest concentrations corresponded to the ICM iomeprol, found at levels between 424 and 2093μgL−1, the analgesic acetaminophen (15–44μgL−1), the diuretic (DIU) furosemide (6–15μgL−1), and the antibiotics (ABIs) ofloxacin and trimethoprim (2–5μgL−1). The lowest levels corresponded to the anti-inflammatory propyphenazone, found at concentrations between 5 and 44ngL−1. Differences in terms of concentrations of the analysed compounds have been observed in all the therapeutic groups when comparing the results obtained in this and other recent studies carried out in hospitals with different characteristics from different geographical areas and in different seasons. The screening level risk assessment performed in raw water from the hospital effluent showed that the analgesics and anti-inflammatories (AAFs) acetaminophen, diclofenac, ibuprofen and naproxen, the antibiotics (ABIs) clarithromycin, ofloxacin and trimethoprim, and the β-blocker (BBL) propranolol were present at concentrations leading to HQ values higher than 10, thus indicating high risk. When applying a factor to take into account potential dilution and degradation processes, only the compound ibuprofen showed a HQ higher than 1. Likewise, the cumulative HQ or Toxic Units (TUs) calculated in the raw water for each of the therapeutic groups studied showed that these three classes of drugs were at concentrations high enough to potentially generate high risk to aquatic organisms while taking into account possible dilution and degradation processes only one of them, the AAFs can be considered to represent high risk. Finally, the environmental hazard assessment performed showed that the AAFs diclofenac and ibuprofen and the ABI clarithromycin have the highest, maximum value of 9 of PBT Index due to their inherent environmentally damaging characteristics of persistence, bioaccumulation and toxicity.The methodology followed in the present case study can be taken as a novel approach to classify and categorize pharmaceuticals on the basis of their occurrence in hospital effluents, their derived environmental risks, and their associated environmental hazard. This classification becomes important because it can be used as a model or orientation for hospitals in the process of developing environmentally sustainable policies and as an argument to justify the adoption of advanced, specific treatments for hospital effluents before being discharged into the public sewage system.

Human health risk assessment, congener specific analysis and spatial distribution pattern of organochlorine pesticides (OCPs) through rice crop from selected districts of Punjab Province, Pakistan

To evaluate the screening level risk assessment of OCPs in rice (Oryza sativa L.) straw (n=20) and rice grains (n=20), samples were collected from different districts of Punjab Province, Pakistan. ∑OCPs' levels (ngg−1) in rice straw and grains ranged from 3.63 to 39.40, 2.72 to 49.89, respectively. DDTs were found predominant over the other detected OCP isomers followed by HCH and heptachlor. Results of one way ANOVA reflected no significant difference for OCPs' levels among sampling sites, except heptachlor for rice grains. ∑OCPs' concentration in rice straw samples was exceeding the minimal residual levels (MRLs) (Australian and Japanese). Results of dietary intake and risk assessment suggested that rice straw is not safe for animals to consume as fodder. Human health was suggested to have some carcinogenic risks by consumption of rice grains, however, no considerable hazardous risk (non-carcinogenic) to human health was found.