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1.

Background

The International Agency for Research on Cancer (IARC) has recently classified glyphosate as a Group 2A ‘probably carcinogenic to humans’. Due to this carcinogenic classification and resulting international debate, there is an increased demand for studies evaluating human health effects from glyphosate exposures. There is currently limited information on human exposures to glyphosate and a paucity of data regarding glyphosate's biological half-life in humans.

Objective

This study aims to estimate the human half-life of glyphosate from human urine samples collected from amenity horticulture workers using glyphosate based pesticide products.

Methods

Full void urine spot samples were collected over a period of approximately 24?h for eight work tasks involving seven workers. The elimination time and estimation of the half-life of glyphosate using three different measurement metrics: the unadjusted glyphosate concentrations, creatinine corrected concentrations and by using Urinary Excretion Rates (UER) (μg L?1, μmol/mol creatinine and UER μg L?1) was calculated by summary and linear interpolation using regression analysis.

Results

This study estimates the human biological half-life of glyphosate as approximately 5 ½, 10 and 7 ¼ hours for unadjusted samples, creatinine corrected concentrations and by using UER (μg L?1, μmol/mol creatinine, UER μg L?1), respectively. The approximated glyphosate half-life calculations seem to have less variability when using the UER compared to the other measuring metrics.

Conclusion

This study provides new information on the elimination rate of glyphosate and an approximate biological half-life range for humans. This information can help optimise the design of sampling strategies, as well as assisting in the interpretation of results for human biomonitoring studies involving this active ingredient. The data could also contribute to the development or refinement of Physiologically Based PharmacoKinetic (PBPK) models for glyphosate.  相似文献   
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ABSTRACT

Background

Reactive balance training (RBT) has been previously found to reduce fall risk in individuals with sub-acute stroke; however, our understanding of the effects of RBT on specific balance impairments is lacking.  相似文献   
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Many characteristics typical of autism, a neurodevelopmental condition characterised by socio‐communicative impairments, are most evident during social interaction. Accordingly, procedures such as the Autism Diagnosis Observation Schedule (ADOS) are interactive and intended to elicit interactional impairments: a diagnosis of autism is given if interactional difficulties are attributed as a persistent quality of the individual undergoing diagnosis. This task is difficult, first, because behaviours can be interpreted in various ways and, second, because conversation breakdown may indicate a disengagement with, or resistance to, a line of conversation. Drawing upon conversation analysis, we examine seven ADOS diagnosis sessions and ask how diagnosticians distinguish between interactional resistance as, on the one hand, a diagnostic indicator and, on the other, as a reasonable choice from a range of possible responses. We find evidence of various forms of resistance during ADOS sessions, but it is a resistance to a line of conversational action that is often determined to be indicative of autism. However, and as we show, this attribution of resistance can be ambiguous. We conclude by arguing for reflexive practice during any diagnosis where talk is the problem, and for a commitment to acknowledge the potential impact of diagnostic procedures themselves upon results.  相似文献   
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Personal care product use is a potential source of metals exposure among children, but studies have been limited. We measured urinary concentrations of 10 metals (aluminum, arsenic [As], barium [Ba], cadmium, cobalt [Co], lead [Pb], manganese [Mn], molybdenum [Mo], nickel, and zinc [Zn]) in third trimester pregnant women (n?=?212) and their children at 8–14 years of age (n?=?250). Demographic factors (child sex, age, socioeconomic status, and maternal education), body mass index (BMI) z-score, and child personal care product use in the 24?h prior to urine collection were examined as predictors of urinary metal concentrations. Metals were detected in 80–100% of urine samples, with significant differences in maternal versus childhood levels. However, metal concentrations were not strongly correlated within or between time points. In linear regression models including all demographic characteristics, BMI z-score, and specific gravity, age was associated with higher Co (6% [95% CI: 2, 10]), while BMI z-score was associated with lower Mo (-6% [95% CI: -11, -1). In addition, significantly higher metal concentrations were observed among users of colored cosmetics (Mo: 42% [95% CI: 1, 99]), deodorant (Ba: 28% [3, 58]), hair spray/hair gel (Mn: 22% [3, 45]), and other toiletries (As: 50% [9, 108]), as well as with an increasing number of personal care products used (As: 7% [3, 11]) after adjustment for child sex, age, total number of products used, and specific gravity. However, significantly lower metal concentrations were noted for users of hair cream (As and Zn: -20% [-36, -2] and -21% [-35, -2], respectively), shampoo (Pb: -40% [-62, -7]), and other hair products (Pb: -44% [-65, -9]). We found that personal care product use may be a predictor of exposure to multiple metals among children. Further research is recommended to inform product-specific exposure source identification and related child health risk assessment efforts.  相似文献   
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