Evaluating the trophic transfer of PCBs from fish to humans: Insights from a synergism of environmental monitoring and physiologically-based pharmacokinetic modeling

Accumulation of polychlorinated biphenyls (PCBs) within fish tissues has prompted many states to issue consumption advisories. In Pennsylvania such advisories suggest one meal per month for most game species harvested from Lake Erie; however, these advisories do not account for the emergent properties of regional PCB mixtures, and the downstream accumulation of PCB congeners into human tissues is poorly documented. This study aimed to demonstrate the utility of pairing environmental monitoring with pharmacokinetic modeling for the purpose of estimating dietary PCB exposure in humans. We qualified and quantified the PCB congeners present in the filets of five Lake Erie fish species and used these data to estimate exposure under consumption scenarios that matched or exceeded the advisories. Physiologically-based pharmacokinetic (PBPK) modeling was then employed to predict PCB accumulation within seven tissue compartments of a hypothetical man and woman over 10 years. Twenty-one congeners were detected between the five fish species at concentrations ranging from 56.0 to 411.7 ng/g. Predicted accumulation in human tissues varied based on tissue type, the species consumed, biological sex, and fish-consumption rate. Notably, steady-state concentrations were higher in fatty tissue compartments ("Fat" and "Liver") and across all tissues in women compared to men. This study serves as a preliminary blueprint for generating predictions of site-specific and tissue-specific exposure through the integration of environmental monitoring and pharmacokinetic modeling. Although the details may vary across applications, this simple approach could complement traditional exposure assessments for vulnerable communities in the Great Lakes region that continue to suffer from legacy contamination.

Unexpected air pollutants with potential human health hazards: Nitrification inhibitors, biocides, and persistent organic substances

To better understand the influence of land use and meteorological parameters on air pollutants, we deployed passive air samplers in 15 regions with different land use in eastern Austria. The samplers consisted of polyurethane PUF and polyester PEF filter matrices, which were analyzed for 566 substances by gas-chromatography/mass-spectrometry. In a previous article, we highlighted a widespread contamination of ambient air with pesticides that depends on the surrounding land use and meteorological parameters. Here we report that, in addition to agricultural pesticides, eight other substances were frequently detected in ambient air: Nitrapyrin, a nitrification inhibitor used to increase nitrogen use efficiency of fertilizers and banned in Austria since 1993; biocides against insects (DEET and transfluthrin) used mainly outside agriculture; piperonyl butoxide (PBO), a synergist mixed into pesticide formulations; and four industrially used polychlorinated biphenyls (PCBs), long banned worldwide. Concentrations of the detected substances were positively related to air temperature, but only slightly related to agricultural land use in the sampler's vicinity. The city center showed the highest concentrations of biocides, PCBs and PBO, but also medium concentrations of nitrapyrin. Four sites had no air contamination with these substances; including two national parks dominated by grassland or forest, but also two sites with mixed land use. The potential human toxicity of the detected substances based on globally harmonized hazard classifications was high: seven substances had specific organ toxicity, six were cancerogenic, and two were acutely toxic; however, several substances had incomplete information of hazard profiles. Moreover, all substances were acutely and chronically toxic to aquatic life. We recommend that substances of different origins be included in the air pollution monitoring portfolio to comprehensively assess the potential hazards to humans and the environment.

Pesticide drift mitigation measures appear to reduce contamination of non-agricultural areas, but hazards to humans and the environment remain

Pesticide drift onto non-agricultural land is a common problem in intensively farmed regions, and national action plans have been established across Europe to prevent it. Here, we analyzed official data on pesticide residues in grass samples collected over six years to determine whether implemented measures to reduce pesticide drift were effective. We used 306 samples collected between 2014 and 2020 on non-agricultural land in one of the most intensively managed apple and wine growing regions in Europe, the Autonomous Province of Bolzano-South Tyrol, Italy. Samples were analyzed for up to 314 substances by gas chromatography and mass spectrometry. Percentage of sites with multiple pesticides and number of pesticides decreased between 2014 and 2020. Fungicides were most often detected, with fluazinam found on 74 % and captan on 60 % of the contaminated sites (53 sites out of a total of 88 sites were contaminated). The most frequently found insecticide, phosmet, was detected in 49 % of the contaminated sites. Only one herbicide, oxadiazon, was detected in <1 % of the sites; glyphosate was not analyzed. The percentage of residues with human hazard properties increased significantly across years regarding reproductive toxicity (from 21 % of the detected substances in 2014 to 88 % in 2020) and specific target organ toxicity (0 % in 2014 to 21 % in 2020). Percentages of substances associated with endocrine-disruption (89 % of substances across years) or carcinogenic properties (45 % of substances across years) remained constant. The percentage of sites where concentrations in grass samples exceeded the surrogate maximum residue levels (MRLs) for lettuce also remained constant. Potential ecotoxicological hazards of detected residues regarding acute contact toxicity to honeybees remained high over the study years, while the acute and chronic toxicity to earthworms decreased. Our results suggest that while drift mitigation measures contributed some reduction in pesticide contamination, they were not sufficient to eliminate substantial risks to human health and the environment in nontarget areas.

Pesticides in ambient air, influenced by surrounding land use and weather, pose a potential threat to biodiversity and humans

Little is known about (i) how numbers and concentrations of airborne pesticide residues are influenced by land use, interactions with meteorological parameters, or by substance-specific chemo-physical properties, and (ii) what potential toxicological hazards this could pose to non-target organisms including humans. We installed passive air samplers (polyurethane PUF and polyester PEF filter matrices) in 15 regions with different land uses in eastern Austria for up to 8 months. Samples were analyzed for 566 substances by gas-chromatography/mass-spectrometry. We analyzed relationships between frequency and concentrations of pesticides, land use, meteorological parameters, substance properties, and season. We found totally 67 pesticide active ingredients (24 herbicides, 30 fungicides, 13 insecticides) with 10-53 pesticides per site. Herbicides metolachlor, pendimethalin, prosulfocarb, terbuthylazine, and the fungicide HCB were found in all PUF samplers, and glyphosate in all PEF samplers; chlorpyrifos-ethyl was the most abundant insecticide found in 93% of the samplers. Highest concentrations showed the herbicide prosulfocarb (725 ± 1218 ng sample^-1), the fungicide folpet (412 ± 465 ng sample^-1), and the insecticide chlorpyrifos-ethyl (110 ± 98 ng sample^-1). Pesticide numbers and concentrations increased with increasing proportions of arable land in the surroundings. However, pesticides were also found in two National Parks (10 and 33 pesticides) or a city center (17 pesticides). Pesticide numbers and concentrations changed between seasons and correlated with land use, temperature, radiation, and wind, but were unaffected by substance volatility. Potential ecotoxicological exposure of mammals, birds, earthworms, fish, and honeybees increased with increasing pesticide numbers and concentrations. Human toxicity potential of detected pesticides was high, with averaged 54% being acutely toxic, 39% reproduction toxic, 24% cancerogenic, and 10% endocrine disrupting. This widespread pesticide air pollution indicates that current environmental risk assessments, field application techniques, protective measures, and regulations are inadequate to protect the environment and humans from potentially harmful exposure.

From properties to toxicity: Comparing microplastics to other airborne microparticles

Microplastic (MP) debris is considered as a potentially hazardous material. It is omnipresent in our environment, and evidence that MP is also abundant in the atmosphere is increasing. Consequently, the inhalation of these particles is a significant exposure route to humans. Concerns about potential effects of airborne MP on human health are rising. However, currently, there are not enough studies on the putative toxicity of airborne MP to adequately assess its impact on human health. Therefore, we examined potential drivers of airborne MP toxicity. Physicochemical properties like size, shape, ζ-potential, adsorbed molecules and pathogens, and the MP's bio-persistence have been proposed as possible drivers of MP toxicity. Since their role in MP toxicity is largely unknown, we reviewed the literature on toxicologically well-studied non-plastic airborne microparticles (asbestos, silica, soot, wood, cotton, hay). We aimed to link the observed health effects and toxicology of these microparticles to the abovementioned properties. By comparing this information with studies on the effects of airborne MP, we analyzed possible mechanisms of airborne MP toxicity. Thus, we provide a basis for a mechanistic understanding of airborne MP toxicity. This may enable the assessment of risks associated with airborne MP pollution, facilitating effective policymaking and product design.

Poisonings in Poland reported to the Polish National Health Fund in the years 2009-2011

BACKGROUND

Poisonings constitute a significant medical, social and economic problem worldwide. In Poland there is no nationwide registry of poisonings, which results in a lack of accurate epidemiological data. Few publications dealing with the problem are based on data obtained from toxicology units and therefore do not include information about cases treated at emergency departments and other non-toxicology units.

METHODS

We analyzed all admissions due to poisonings reported to the Polish National Health Fund by all hospital units in Poland in the 2009-2011 period. Diagnoses were encoded according to the ICD-10 classification.

RESULTS

A total of 254,425 admissions were reported, 85,398 in 2009, 85,230 in 2010 and 83,797 in 2011. The male to female ratios were 1.88, 1.75 and 1.80 respectively. The most frequent causes of admissions were poisonings with ethanol (n = 121,874; 47.9%), carbon monoxide (n = 17,179; 6.8%) and benzodiazepines (n = 10,340; 4.1%). Alcohols were the reason for 104,680 admissions in men (63.2%) and 22,612 admissions in women (25.5%; p < 0.01). Poisonings with pharmaceuticals and other drugs were reported in 34,616 men (20.9%) and 45,238 women (51%; p < 0.01). There were 1680 cases of fatal poisonings in the analyzed period. The hospital mortality due to poisonings increased from 1.1% in 2009 to 1.5% in 2011 (p < 0.01). The mortality in general Intensive Care Units increased from 14.4% in 2009 to 22.3% in 2011 (p < 0.01). The etiology of fatal poisonings was highly dependent on the type of hospital unit.

CONCLUSIONS

The overall number of admissions due to poisonings decreased slightly during the study period, but they remained a significant cause of morbidity and mortality. Alcohols were the main cause of admissions in the analyzed period. Alcohol intoxications were more frequent in men while poisonings with pharmaceuticals were more frequent in women. Carbon monoxide exposures were a significant cause of morbidity and mortality in the studied period in Poland. A national poison information and toxicovigilance system should be created in Poland, ideally allowing for near real-time monitoring of cases of poisonings.

Endosulfan poisoning: An overview

Endosulfan, an organochlorine (OC) insecticide, is a widely used agricultural pesticide, despite its life threatening toxic effects. In this review, the pharmacokinetics of endosulfan, mechanism of endosulfan toxicity, clinical presentations and management, histopathological findings, and toxicological analysis are described, in addition to its environmental toxicity. The toxic effects of endosulfan can affect many organs and systems presenting in a wide array of signs and symptoms. Although termed a restricted OC-classed pesticide, it continues to be used, especially in the developing world, owing to its beneficial effects on agriculture. Several cases of endosulfan poisoning have been reported from different regions of the world. Whether accidental or intentional, endosulfan ingestion proves to be fatal unless immediate, aggressive treatment is initiated. Management is mainly supportive as no antidote exists for endosulfan poisoning as yet. The use of endosulfan needs to be strictly regulated and eventually banned worldwide altogether to lower the current morbidity and mortality resulting from this pesticide. Additionally, monitoring biological samples, using non-invasive techniques such as breast milk sampling, can provide an effective method of observing the elimination of this environmentally persistent organic pollutant from the general population.

Dietary supplementation of coenzyme Q10 plus multivitamins to hamper the ROS mediated cisplatin ototoxicity in humans: A pilot study

Oxidative stress exerts major role in the pathogenesis of side effects of many antineoplastic drugs, including ototoxicity of cisplatin. In particular, increased levels of reactive oxygen species (ROS) represent one of the molecular mechanisms underlying the apoptosis of different types of hearing cells. Antioxidants and ROS scavengers may thus represent potential therapeutic options to prevent platinum-associated ototoxicity.

The aim of this preliminary case-control study was to explore the efficacy of a dietary antioxidant supplement, in order to hamper the occurrences of ototoxicity in patients undergoing cisplatin chemotherapy.

As results, a significant protection against cochlear toxic damage was demonstrated in patients who took the antioxidant supplement, which furthermore prevented the occurrence of hearing disorders and tinnitus. These clinical evidences were corroborated by the oxidative status of patients. After cisplatin chemotherapy, the plasma derivatives of reactive oxygen metabolites (d-ROMs) content rapidly increased in control patients, but it was maintained in those under dietary supplementation, likely because of a higher anti-ROMs potential. Indeed, an increment in rapid anti-ROMs was detected in supplemented patients, though no differences were highlighted in terms of slow anti-ROMs.

In conclusion, in this preliminary report we demonstrated the feasibility of a dietary antioxidant supplementation in order to prevent the cisplatin induced hearing damage.

Comparison of VAERS fetal-loss reports during three consecutive influenza seasons: was there a synergistic fetal toxicity associated with the two-vaccine 2009/2010 season?

The aim of this study was to compare the number of inactivated-influenza vaccine–related spontaneous abortion and stillbirth (SB) reports in the Vaccine Adverse Event Reporting System (VAERS) database during three consecutive flu seasons beginning 2008/2009 and assess the relative fetal death reports associated with the two-vaccine 2009/2010 season. The VAERS database was searched for reports of fetal demise following administration of the influenza vaccine/vaccines to pregnant women. Utilization of an independent surveillance survey and VAERS, two-source capture–recapture analysis estimated the reporting completeness in the 2009/2010 flu season. Capture–recapture demonstrated that the VAERS database captured about 13.2% of the total 1321 (95% confidence interval (CI): 815–2795) estimated reports, yielding an ascertainment-corrected rate of 590 fetal-loss reports per million pregnant women vaccinated (or 1 per 1695). The unadjusted fetal-loss report rates for the three consecutive influenza seasons beginning 2008/2009 were 6.8 (95% CI: 0.1–13.1), 77.8 (95% CI: 66.3–89.4), and 12.6 (95% CI: 7.2–18.0) cases per million pregnant women vaccinated, respectively. The observed reporting bias was too low to explain the magnitude increase in fetal-demise reporting rates in the VAERS database relative to the reported annual trends. Thus, a synergistic fetal toxicity likely resulted from the administration of both the pandemic (A-H1N1) and seasonal influenza vaccines during the 2009/2010 season.