Nanoplastics and Arsenic Co-Exposures Exacerbate Oncogenic Biomarkers Under an in Vitro Long-Term Exposure Scenario

Background The increasing accumulation of plastic waste and the widespread presence of its derivatives, micro- and nanoplastics (MNPLs), call for an urgent evaluation of their potential health risks. In the environment, MNPLs coexist with other known hazardous contaminants and, thus, an interesting question arises as to whether MNPLs can act as carriers of such pollutants, modulating their uptake and their harmful effects. In this context, we have examined the interaction and joint effects of two relevant water contaminants: arsenic and polystyrene nanoplastics (PSNPLs), this last being a model of nanoplastic. Methods Since both agents are persistent pollutants, the potential effects have been evaluated under a chronic exposure scenario and measuring different effect biomarkers involved in the cell transformation process. Thus, cells previously transformed by chronic arsenic exposure were further exposed to PSNPLs, arsenic, and the combination PSNPLs/arsenic for 12 weeks. Results Interestingly, a physical interaction between both pollutants was demonstrated by using TEM/EDX methodologies. Results also indicate that the continuous co-exposure enhances the DNA damage and the aggressive features of the initially transformed phenotype. Remarkably, co-exposed cells present a higher proportion of spindle-like cells within the population, an increased capacity to grow independently of anchorage, as well as enhanced migrating and invading potentials when compared to cells exposed to arsenic or PSNPLs alone. Conclusions This study highlights the need for further studies exploring the long-term effects of contaminants of emerging concern such as MNPLs, and the importance of considering the behavior of mixtures as part of the hazard and human risk assessment approaches.

Human Health Risk Assessment of Air Pollution in the Regions of Unsustainable Heating Sources. Case Study—The Tourist Areas of Southern Poland

Air pollution is one of the main factors affecting human health. Air quality is especially important in the tourist areas developed with facilities for outdoor activities. During the winter season of 2017/2018, the concentrations of particulate matter (PM10, PM2.5, PM1), CO, O3, and NO2 were studied in 12 attractive tourist villages in the surroundings of the Czorsztyn Reservoir in southern Poland. Air pollutant measurements were performed continuously, using a single ground-based Alphasense air sensor. Our assessment of human health risk (HHRA), arising from inhalation exposure to air contaminants, was calculated for both local inhabitants and tourists, based on actual measured values. It was found that pollutant concentrations exceeded both permissible and recommended levels of PM10 and PM2.5. The mean total noncarcinogenic risk values were equal to 9.58 (unitless) for adults and 9.68 (unitless) for children and infants, under the resident exposure scenario. However, under the tourist exposure scenario, the mean total risk was equal to 1.63 (unitless) for adults and 1.64 (unitless) for children and infants. The risk to tourists was lower than that to inhabitants due to shorter exposure times. The target non-carcinogenic value of 1, calculated for PM10, PM2.5, and NO2, was significantly exceeded in total risk, under the residential exposure scenario, in reference to all the local subpopulations. In the majority of the investigated locations, the total risk exceeded the value of 1, under the tourist scenario, for all the subpopulations analysed. PM2.5 was recognised to be the most important contaminant in our risk analysis, in view of its share in the total risk value.

Effects of Incubation of Human Brain Microvascular Endothelial Cells and Astrocytes with Pyridostigmine Bromide, DEET, or Permethrin in the Absence or Presence of Metal Salts

Gulf War Illness (GWI) is a chronic, multi-symptom illness suffered by over one-third of American military veterans who served in the Persian Gulf War between 1990 and 1991. No current single-exposure scenario accounts for all the symptoms observed in GWI, and instead may be due to a multi-exposure scenario. As a larger effort to understand how one category of multi-exposure scenarios of organic compounds such as nerve gas prophylactic pyridostigmine bromide, or insecticides/pesticides such as N,N-diethyl-m-toluamide (DEET) and permethrin, plus heavy metals found in inhaled dust particles (Al, Fe, Ni, Sr, DU, Co, Cu, Mn, and Zn) might play a role in neural aspects of GWI, we begin this initial study to examine the toxicity and oxidative damage markers of human brain endothelial cell and human astrocyte cell cultures in response to these compounds. A battery of cytotoxicity assessments, including the MTT assay, Neutral Red uptake, and direct microscopic observation, was used to determine a non-toxic dose of the test compounds. After testing a wide range of doses of each compound, we chose a sub-toxic dose of 10 µM for the three organic compounds and 1 µM for the nine metals of interest for co-exposure experiments on cell cultures and examined an array of oxidative stress-response markers including nitric oxide production, formation of protein carbonyls, production of thiobarbituric acid-reactive substances, and expression of proteins involved in oxidative stress and cell damage. Many markers were not significantly altered, but we report a significant increase in nitric oxide after exposure to any of the three compounds in conjunction with depleted uranium.

Examining the Impact of Inter-provincial Migration on Environmental Health in China

Background China has a large volume of inter-provincial migrants, accounting for more than 11% of the total population. The economic benefits of inter-provincial migration have been well studied, whereas the health impacts related to environmental factors are generally ignored. Methods In this study, we use 1% national population sampling survey data from 2015 and daily PM2.5 (particles ≤ 2.5 µm in aerodynamic diameter) concentration data from 360 cities to analyze the health benefits associated with air pollution due to inter-provincial migration. The exposure-response function was used to estimate the economic value of these health benefits via the adjusted-human-capital and cost-of-illness methods. Results Considering a full-exposure scenario, inter-provincial migration resulted in a reduction in the PM2.5 exposure concentration of 3.94 µg/m3 in 2015, corresponding to a reduction of 6114 premature deaths, 233.4 thousand hospitalization cases, and 1.5 million asthma attacks. The corresponding economic value of these health benefits was about 10.44 billion yuan (0.02% of the national GDP in 2015). A protection scenario, assuming that the migrants protected themselves from air pollution, showed very similar results to the full-exposure scenario (PM2.5 exposure reduced by 3.60 µg/m3); hence, personal protection does not reduce significantly the health risks of air pollution. Conclusions At the national level, the labor force obtains both economic and health benefits. However, a high number of migrants flow out of the central region of China result in a labor deficiency and social imbalance. Migration to large cities provides economic benefits at the expense of health. Environmental migration becomes an increasingly important motivation for inter-provincial migration, which places new pressure on policy makers to consider social welfare and environmental protection in the provinces.

Volatile Organic Compound (VOC) Emissions from a Personal Care Polymer-Based Item: Simulation of the Inhalation Exposure Scenario Indoors under Actual Conditions of Use

Polymer-based items may release Volatile Organic Compounds (VOCs) and odors indoors, contributing to the overall VOC inhalation exposure for end users and building occupants. The main objective of the present study is the evaluation of short-term inhalation exposure to VOCs due to the use of a personal care polymer-based item, namely, one of three electric heating bags, through a strategic methodological approach and the simulation of a ‘near-to-real’ exposure scenario. Seventy two-hour test chamber experiments were first performed to characterize VOC emissions with the items on ‘not-heating mode’ and to derive related emission rates. The polyester bag was revealed to be responsible for the highest emissions both in terms of total VOC and naphthalene emissions (437 and 360 µg/m3, respectively), compared with the other two bags under investigation. Complementary investigations on ‘heating mode’ and the simulation of the exposure scenario inside a 30 m3 reference room allowed us to highlight that the use of the polyester bag in the first life-cycle period could determine a naphthalene concentration (42 µg/m3) higher than the reference Lowest Concentration of Interest (LCI) value (10 µg/m3) reported in European evaluation schemes. The present study proposes a strategic methodological approach highlighting the need for the simulation of a realistic scenario when potential hazards for human health need to be assessed.