Exploring the impact of polystyrene microplastics on human health: unravelling the health implications of polystyrene microplastics (PS-MPs): a comprehensive study on cytotoxicity, reproductive health, human exposure, and exposure assessment

This investigation explores the various impacts that polystyrene microplastics (PS-MPs) have on human health. As most of the plastic materials affect human health when they release leachable toxic substances that affect human health, this causes a negative effect that determines poor health conditions and leads to health hazards associated with plastic toxins routed in the human body, such as: Polychlorinated Biphenyls, Polybrominated Biphenyls etc. The study includes micro-plastic exposure assessment on testicular structure analysis, and cytotoxicity evaluations of different human cell types. The findings clarified the possible dangers of PS-MPs exposure from food, medications, and common products, emphasising the necessity of standard specimen handling procedures for precise biomonitoring.

Comparison of Biomarkers of Exposure in a Controlled Study of Smokers Switched from Conventional Cigarettes to Heated Tobacco Products

The heated tobacco product (HTP) heats rather than burns tobacco to release an aerosol with significantly fewer toxicants than conventional cigarette smoke and has received global attention in recent years. To investigate whether changes in biomarkers of exposure could be detected after switching from conventional cigarettes (CCs) to HTPs, 224 subjects from four cities in China participated in this study. Nine biomarkers containing tobacco-specific nitrosamines (TSNAs), volatile organic compounds (VOCs), and the biomarkers for acrolein and crotonaldehyde were determined by UPLC-MS/MS. The levels of the sum of nine biomarkers in CCs were 5.4 and 5.2 times higher than in an Original-HTP and Menthol-HTP, respectively. Among the nine biomarkers, 3HPMA and 3HMPMA accounted for the highest proportions. Switching from CCs to HTPs is good for both men and women because the changes in each biomarker in urine samples were the same in men and women. Among all the subjects, subjects aged 20-39 years had the greatest reduction in biomarker residues in urine. The findings of the present study provided useful information for the health risk research of HTPs in China.

Dietary Exposure to Toxic Elements and the Health of Young Children: Methodological Considerations and Data Needs

Concerns have been raised regarding toxic-element (arsenic, cadmium, lead, and mercury) contamination of commercially available infant foods around the world. Young children are vulnerable to the effects of toxic elements, based on higher absorption levels and potentially poorer detoxification capacities. Toxic-element exposures in early life exact high societal costs, but it is unclear how much dietary exposure to these elements contributes to adverse health outcomes. Well-designed epidemiological studies conducted in different geographical and socioeconomic contexts need to estimate dietary toxicant exposure in young children and to determine whether causal links exist between toxicants in children's diets and health outcomes. This commentary outlines the methodological considerations and data needs to advance such research.

The Influence of Parental Environmental Exposure and Nutrient Restriction on the Early Life of Offspring Growth in Gambia-A Pilot Study

BACKGROUND

The role of the germline in epigenetic transgenerational inheritance starts with environmental factors, acting on the first generation of a gestating mother. These factors influence the developing second-generation fetus by altering gonadal development, thereby reprogramming the primordial germ cell DNA methylation and leading to consequences that might be seen along generations.

OBJECTIVE

Despite these epigenetic factors now surfacing, the few available studies are on animal-based experiments, and conducting a follow-up on human intergenerational trials might take decades. To this response, this study aimed to determine the influence of parental energy, toxicant exposure, age, and nutrient restriction on the early life of offspring growth in Gambia.

METHOD

This pilot study was based on population observation and combined both maternal and paternal factors across the country between August and October 2021. It captures the lifestyle and health detailed account of 339 reproductive parents and their last born (child under 5 years) using a structured interview questionnaire performed by nurses and public health officers.

RESULTS

This study showed that parents who worked in industrial areas were more likely to have offspring with poor psychosocial skills. In addition, mothers who are exposed to oxidative stress and high temperatures are more likely to have offspring with poor psychosocial skills. Mothers who consume a high-protein diet were almost three times more likely to have infants with good psychosocial skills in their offspring. Furthermore, there was a negative correlation between maternal stress during pregnancy and the psychosocial skills of offspring.

CONCLUSION

This study was able to ascertain if the maternal diet during gestation, toxicant exposure, maternal stress, and parental smoking habits have an influence on the early life of offspring. While the study recommends a large sample size study to eliminate selection bias, there should be an increased level of awareness of mothers of their offspring's health and their husbands' lifestyles that might influence the adulthood health of their offspring.

Systematic Evaluation of the Effects of Toxicant Exposure on Survival in Zebrafish Embryos and Larvae

The use of whole animal models in toxicological studies is essential for understanding the physiological responses caused by chemical exposures. However, such studies can face reproducibility challenges due to unaccounted experimental parameters that can have a marked influence on toxicological outcomes. Zebrafish embryos and larvae are a popular vertebrate animal model for studying cellular, tissue, and organ responses to toxicant exposures. Despite the popularity of this system, standardized protocols that control for the influence of various experimental parameters and culture conditions on the toxicological response in these animals have not been widely adopted, making it difficult to compare findings from different laboratories. Here, we describe a detailed approach for designing and optimizing protocols to assess the impact of chemical exposures on the development and survival of zebrafish embryos and larvae. We first describe our standard procedure to determine two key toxicological thresholds, the maximum tolerable concentration (MTC) and the lethal concentration (LC₅₀ , defined as that in which 50% of larvae die), in response to an exposure that persists from early development through larval maturation. We then describe two protocols to systematically test how key experimental parameters, including genetic background, culture media, animal density, volume, plate material, and developmental stage in which the embryos are exposed, alter the MTC and LC₅₀ . Finally, we provide a step-by-step guide to assess the interaction between two chemicals using this model. These protocols will guide the standardization of toxicological studies using zebrafish and maximize reproducibility. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Zebrafish embryo collection and culture, and establishment of the MTC and LC₅₀ Basic Protocol 2: Evaluation of the impact of culture conditions on toxicant responses of zebrafish embryo and larvae Basic Protocol 3: Identification of the developmental window of sensitivity to toxicant exposure Basic Protocol 4: Testing interaction between multiple toxicants.

Differences in puff topography, toxicant exposure, and subjective response between waterpipe tobacco smoking men and women

Waterpipe tobacco smoking (WTS) exposes users to toxicants in much greater amounts than a cigarette. Little is known about how gender affects WTS toxicant exposure and subjective response. Data from three WTS clinical laboratory studies were combined for analysis. Participants (N = 99; 38 women) completed a 45-min WTS session where they smoked a waterpipe ad libitum. Puff topography was measured throughout, and plasma nicotine concentration, expired air carbon monoxide (CO), and subjective responses were measured pre- and post-WTS. There was a gender effect for total puff volume with men inhaling a greater smoke volume, on average (M = 59.9 L, SD = 40.7), compared with women (M = 38.8 L, SD = 27.8; p < .01). Men had greater post-WTS mean plasma nicotine concentrations (M = 10.0 ng/ml, SD = 7.1) compared with women (M = 6.9 ng/ml, SD = 5.2; p < .05). Post-WTS expired air CO was not associated with gender (men M = 27.6 ppm, SD = 18.9; women M = 22.7 ppm, SD = 17.0, ns). Relative to men, women had higher post-WTS scores for subjective measures of "nauseous," "dizzy," "nervous," "headache," and "heart pounding." Men and women are exposed to toxicants during WTS, and men may achieve higher nicotine exposure than women, likely resulting from differences in smoke inhaled. However, similar post-WTS expired air CO between men and women and higher ratings of negative subjective responses among women may indicate that factors beyond puff topography may impact toxicant exposure and subjective response to WTS. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Smokeless tobacco brand switching: a means to reduce toxicant exposure?

The purpose of this study was to examine the effects of smokeless tobacco (ST) brand switching on biomarkers of ST exposure and on ST use. Subjects seeking treatment to reduce their use were randomized to ST brand switching with controlled ST topography, brand switching with ad libitum ST use, or a waitlist control with subsequent randomization to one of these two conditions. The waitlist control group was included to assess whether changes were a consequence of time effect. During the intervention, Copenhagen or Kodiak ST users were asked to switch to products that were sequentially lower in nicotine content: Skoal Long Cut Straight or Wintergreen for 4 weeks and then Skoal Bandits for the subsequent 4 weeks. Measures were obtained during the course of treatment and at 12-week follow-up. Significant reductions in total urinary cotinine and 4-(methylnitrosamino)-L-(3-pyridyl)-L-butanol (NNAL) plus its glucuronides (total NNAL) were observed with no significant differences between the controlled topography and ad libitum conditions. Significant reductions were also observed in the amount and duration of dips with a significant intervention effect for durational measures. At 12 weeks, the 7-day biochemically-verified tobacco abstinent rate was 26% in the ad libitum group. ST brand switching may be a feasible alternative intervention for ST users interested in quitting but unwilling to stop ST use completely.