Suchergebnisse

Abstract
Background
Endocrine disrupting chemicals have been identified for a number of human endocrine systems, but there are no reports on vitamin D-antagonistic activities in environmental samples.

Objectives
We have investigated if there are compounds present in the environment that can act as Vitamin D receptor (VDR) antagonists.

Methods
Water samples were collected of the influent and effluent water from five Swedish wastewater treatment facilities and concentrated with solid phase extraction. VDR antagonistic properties of the samples were tested with a cell-based in vitro assay responsive to vitamin D signaling. Cytotoxicity was monitored by three different assays.

Results
We observed a dose-dependent decrease in the VDR signaling in most studied samples, although the effect was overlapping with cytotoxicity for the influent samples. For effluent samples, we observed clear VDR antagonistic effects also in non-cytotoxic concentrations. The observed effects could not be explained by presence of natural organic matter or cadmium in the water.

Discussion
The vitamin D endocrine system regulates a broad range of physiological processes, and disruption of this system could be associated with serious health consequences. In this study, we report environmental presence of compounds with VDR antagonistic properties, compounds which constitute a new group of potential endocrine disruptors. The VDR antagonism was observed in wastewater treatment facility effluent waters, which are discharged into water systems used as raw water for drinking water production. The findings reported in this study may indicate a potential hazard to human health and aquatic life. Future research is needed to investigate the presence of VDR antagonists in the environment, identification of the causative compounds, and studies of exposure of humans and aquatic organisms to these compounds.

An amendment to this paper has been published and can be accessed via the original article.

Abstract
Background
Contamination of drinking water by hazardous chemicals can be associated with human health risks. Recent studies using effect-based in vitro methods have demonstrated that a large part of the observed toxic effects are caused by unknown chemicals. In this study, we have used a panel of effect-based methods to study the presence of chemical contaminants in a unique material; glass-bottled Swedish tap water collected during the 1990s. These water samples were compared to drinking water from the same source waters and drinking water facilities, yet collected about 25 years later, in 2020.

Results
Samples were concentrated by solid phase extraction and evaluated for the following activities; estrogen receptor activity, androgen receptor activity, antiandrogenic activity, aryl hydrocarbon receptor activity, and oxidative stress response. We observed aryl hydrocarbon receptor activities in almost all studied samples and estrogen receptor activity in three out of ten studied samples. No activities were observed for androgen receptor activity, antiandrogenic activity or oxidative stress response. In general, observed activities were more frequent and higher in the water samples collected during the 1990s as compared to the corresponding samples collected in 2020.

Conclusions
This study demonstrates that it is possible to conduct an effect-based evaluation of the presence of hazardous chemicals in drinking water, with as small starting volume as 330 mL, by using miniaturized bioassays. Further, by comparing the glass-bottled water samples with newly collected water samples from the same drinking water treatment facilities, our results indicate that the presence of aryl hydrocarbon receptor and estrogen receptor activating compounds in the drinking water has decreased over the approximately quarter of a century that is separating the two sampling occasions. This difference could be due to improved raw water quality and/or improved treatment efficiency in the treatment plants.

Abstract
Background
Bioanalytical tools have been shown to be useful in drinking water quality assessments. Here, we applied a panel of in vitro bioassays to assess the treatment efficiency of two pilot-scale treatments: ozonation and granular activated carbon (GAC) filtration at a drinking water treatment plant (DWTP). The pilot-scale systems were studied alongside a full-scale treatment process consisting of biological activated carbon (BAC) filtration, UV disinfection, and monochloramine dosing. Both systems were fed the same raw water treated with coagulation/flocculation/sedimentation and sand filtration. The endpoints studied were oxidative stress (Nrf2 activity), genotoxicity (micronuclei formations), aryl hydrocarbon receptor (AhR) activation, as well as estrogen receptor (ER) and androgen receptor (AR) activity.

Results
Nrf2, AhR, and ER activities and genotoxic effects were detected in the incoming raw water and variability was observed between the sampling events. Compared to most of the samples taken from the full-scale treatment system, lower Nrf2, AhR, and ER bioactivities as well as genotoxicity were observed in all samples from the pilot-scale systems across all sampling events. The most pronounced treatment effect was a 12-fold reduction in Nrf2 activity and a sixfold decrease in micronuclei formations following ozonation alone. GAC filtration alone resulted in sevenfold and fivefold reductions in Nrf2 activity and genotoxicity, respectively, in the same sampling event. Higher bioactivities were detected in most samples from the full-scale system suggesting a lack of treatment effect. No androgenic nor anti-androgenic activities were observed in any sample across all sampling events.

Conclusions
Using effect-based methods, we have shown the presence of bioactive chemicals in the raw water used for drinking water production, including oxidative stress, AhR and ER activities as well as genotoxicity. The currently used treatment technologies were unable to fully remove the observed bioactivities. Ozonation and GAC filtration showed a high treatment efficiency and were able to consistently remove the bioactivities observed in the incoming water. This is important knowledge for the optimization of existing drinking water treatment designs and the utilization of alternative treatment technologies.

AbstractDrinking water producers have a far-reaching responsibility to provide safe, clean and wholesome drinking water, using water resources possibly effected by the thousands of chemicals used in societies' daily life. This study has monitored chemical hazards in drinking water from source to tap, using effect-based methods. The study was conducted at a Swedish drinking water treatment plant sourcing lake water and aimed to investigate potential seasonal variations in both the raw water and water after different treatment steps. Furthermore, a granular activated carbon (GAC) pilot facility was evaluated. Samples were analyzed for estrogenicity, androgenicity, aryl hydrocarbon receptor (AhR) activity, oxidative stress (Nrf2) response and genotoxicity (micronucleus formation). We observed seasonal differences in oxidative stress and genotoxic effects in both raw and drinking water with higher activities during the late fall of each year. The removal efficiency for both oxidative stress and genotoxicity was limited in the full-scale treatment process and occasionally the genotoxicity was also detected in outgoing drinking water from the treatment plant and in samples collected at consumers tap on the distribution network. AhR activity was present in all raw water samples and the removal was limited. Estrogenic activities were observed in most of the raw water samples but in contrast to the other parameters estrogenicity was effectively reduced by the full-scale conventional treatment. The GAC pilot treatment was generally more efficient than the full-scale conventional treatment in removing all observed bioactivities and could be a viable complement to the current treatment to assure drinking water free from genotoxic compounds. Genotoxic activities in drinking water was observed while all currently regulated chemical parameters were fulfilled. This highlights the need for effect-based monitoring in efforts to ensure the chemical safety of drinking water, as target chemical analysis of single compounds will overlook both unknown hazardous compounds as well as potential mixture effects.
Graphical Abstract

Abstract
Background
Fresh water bodies represent less than 1% of overall amount of water on earth and ensuring their quality and sustainability is pivotal. Although several campaigns have been performed to monitor the occurrence of micropollutants by means of chemical analysis, this might not cover the whole set of chemicals present in the sample nor the potential toxic effects of mixtures of natural and anthropogenic chemicals. In this sense, by selecting relevant toxicity endpoints when performing in vitro bioanalysis, effect-based methodologies can be of help to perform a comprehensive assessment of water quality and reveal biological activities relevant to adverse health effects. However, no prior bioanalytical study was performed in wetland water samples from the Spanish Mediterranean coastline.

Methods
Eleven samples from relevant water bodies from the Spanish Mediterranean coastline were collected to monitor water quality on 8 toxicity endpoints. Aryl hydrocarbon receptor (AhR), androgenicity (AR+ and AR−), estrogenicity (ER+ and ER−), oxidative stress response (Nrf2) and vitamin D receptor (VDR+ and VDR−) reporter gene assays were evaluated.

Results
AhR was the reporter gene assay showing a more frequent response over the set of samples (activated by 9 out of 11 samples), with TCDD-eq in the range 7.7–22.2 pM. For AR, ER and VDR assays sporadic activations were observed. Moreover, no activity was observed on the Nrf2 reporter gene assay. Wastewater and street runaway streams from Valencia could be responsible for enhanced activities in one of the water inputs in the Natural Park 'L'Albufera'.

Conclusions
Water quality of relevant wetlands from the Spanish Mediterranean coastline has been evaluated. The utilization of a panel of 5 different bioassays to cover for different toxicity endpoints has demonstrated to be a good tool to assess water quality.

Abstract
Background
Food contact articles are used in our everyday life and information regarding the potential health hazards of migrating chemicals for humans is scarce. In this study, an effect-based evaluation of non-polar extracts of food contact articles made of paper and board was conducted with a panel of eight bioassay endpoints. These, health-relevant endpoints, included oxidative stress, inflammation, genotoxicity, xenobiotic metabolism and hormone receptor effects.

Results
In total, 62 food contact articles were pooled into 19 groups, in which articles intended to be used for similar types of food item(s) were pooled, and extracted with acetone:n-hexane (1:4). These were then tested in the effect-based bioassays. Bioactivities were detected for multiple materials in six out of eight assays, the two assays showing no effects were NFκB and androgen receptor agonistic response. In essence, the detection rates of the tested non-polar extracts were 72% for antagonistic effects on the estrogen receptor, 72% for antagonistic effects on the androgen receptor, 47% for oxidative stress, 28% for agonistic effects on the estrogen receptor and 33% for genotoxicity. The bioequivalent concentrations ranges in extracts of 10 mg food contact article/mL cell culture media were: for oxidative stress from 2.45 to 5.64 µM tBHQ equivalents, estrogen receptor agonistic activity from 1.66 to 6.33 ρM estradiol equivalents, estrogen receptor antagonistic activity from 1.21 × 10–3 to 4.20 × 10–3 μM raloxifene equivalents and androgen antagonistic activity 0.08–0.46 μM hydroxyflutamide equivalents. The extracts that were bioactive in multiple assays were: baking moulds, boxes for popcorn, infant formula/skimmed milk, porridge/flour mixes, pizza, fries' and hamburgers as well as packages for frozen food.

Conclusion
Non-polar extracts of food contact articles contain compounds that can activate molecular initiating events in toxicity pathways of high relevance to human health. These events included endocrine-disruptive activities, oxidative stress and genotoxicity. Effect-based methods proved to be a valuable tool for evaluating food package articles, as they can detect potentially hazardous effects of both known and unknown chemicals as well as potential cocktail effects.

Abstract

Background
Pesticide residue contamination of surface water in agricultural areas can have adverse effects on the ecosystem. We have performed an integrated chemical and bioanalytical profiling of surface water samples from Swedish agricultural areas, aiming to assess toxic activity due to presence of pesticides. A total of 157 water samples were collected from six geographical sites with extensive agricultural activity. The samples were chemically analyzed for 129 commonly used pesticides and transformation products. Furthermore, the toxicity was investigated using in vitro bioassays in the water samples following liquid–liquid extraction. Endpoints included oxidative stress response (Nrf2 activity), estrogen receptor (ER) activity, and aryl hydrocarbon receptor (AhR) activity. The bioassays were performed with a final enrichment factor of 5 for the water samples. All bioassays were conducted at non-cytotoxic conditions.


Results
A total of 51 pesticides and transformation products were detected in the water samples. Most of the compounds were herbicides, followed by fungicides, insecticides and transformation products. The highest total pesticide concentration in an individual sample was 39ʵg/L, and the highest median total concentration at a sample site was 1.1ʵg/L. The largest number of pesticides was 31 in a single sample. We found that 3% of the water samples induced oxidative stress response, 23% of the samples activated the estrogen receptor, and 77% of the samples activated the aryl hydrocarbon receptor. Using Spearman correlation coefficients, a statistically significant correlation was observed between AhR and ER activities, and AhR activity was strongly correlated with oxidative stress in samples with a high AhR activity. Statistically significant relationships were observed between bioactivities and individual pesticides, although the relationships are probably not causal, due to the low concentrations of pesticides. Co-occurrence of non-identified chemical pollutants and naturally occurring toxic compounds may be responsible for the induced bioactivities.


Conclusions
This study demonstrated that integrated chemical analysis and bioanalysis can be performed in water samples following liquid/liquid extraction with a final enrichment factor of 5. AhR and ER activities were induced in water samples from agricultural areas. The activities were presumably not caused by the occurrence of pesticides, but induced by other anthropogenic and natural chemicals.

The Panel on Food Additives and Flavourings of the European Food Safety Authority was requested to deliver a scientific opinion on the implications for human health of the product Grill flavour concentrate (vegetable) [FL‐no: 21.002] in the Flavouring Group Evaluation 501 (FGE.501), according to Regulation (EC) No 1331/2008 and Regulation (EC) No 1334/2008 of the European Parliament and of the Council. The product is derived from heat‐treated canola oil and intended to be used as a food flavouring with grilled aroma in a wide variety of food categories. Information on manufacturing and compositional data was considered adequate to show the reproducibility of the production process. The chronic dietary exposure to the substance estimated using the added portions exposure technique (APET) was calculated to be 0.402 and 0.252 mg/person per day for a 60‐kg adult and for a 15‐kg child, respectively. Based on exposure estimate and the results from the repeated‐dose toxicity studies, a sufficient margin of safety could be calculated. However, the Panel noted that for six constituents of the flavouring there is an indication for genotoxicity. Therefore, these six substances have to be further considered. Until these evaluations have been finalised the safety of Grill flavour concentrate (vegetable) cannot be fully assessed.