Children's diets,pesticide uptake,and implications for risk assessment: An Israeli case study

The presence of pesticides in the Israeli food supply is well documented but little is known about the risks posed by children's diets for potential exposures. We investigated potential exposures to food-borne pesticides in a sample of 301 urban Israeli children (2008–10). Data from a food frequency questionnaire, 24 hour food recall, and Israel's national pesticide monitoring program were used to estimate uptake factors for 26 compounds in 27 fruits and vegetables. A pilot risk assessment was performed and the findings were compared with the Israel Ministry of Health's 2012 pesticide risk assessment for the general population. The surveyed children had higher potential exposures than the general population for over one third of the compounds, and uptake factors exceeded the Acceptable Daily Intake in ten compounds. Methamidophos, exceeded the ADI at the 25th percentile and fenamiphos, iprodione, and oxydemethon methyl, exceeded the ADI at the 50 percentile. ADIs for several compounds were exceeded even though the residues detected were below the statutory limit. Improved monitoring, enforcement, and revision of the Maximum Residue Limit for certain food/pesticide pairs are indicated as is the need to incorporate data on children's actual food consumption in national risk assessments.     

Demonstration of a modelling-based multi-criteria decision analysis procedure for prioritisation of occupational risks from manufactured nanomaterials

Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables.     

Opportunities and barriers to effective operation and maintenance of public toilets in informal settlements: perspectives from toilet operators in Kampala

Although classified by the Joint Monitoring Programme (JMP) as unimproved sanitation facilities, public toilets still play a critical role in eliminating open defecation in informal settlements. We explored perspectives of toilet operators on opportunities and barriers to operation and maintenance (O&M) of public toilets in informal settlements. A cross-sectional study design was used. Up to 20 in-depth interviews were used to obtain data on the experiences of public toilet operators. Thematic content analysis was used.

Ressults show that opportunities for improving O&M include; operation of public toilets is a source of livelihood; operators are knowledgeable on occupational risks, and the community is involvedin sanitation activities. Barriers to effective O&M include; high operation costs, failure to break even and a lack of investments in occupational health Therefore, there is need to recognise the significance of public toilets as a viable alternative to open defecation in areas where ownership of private sanitation facilities is difficult. Failure to observe the health and safety of toilet operators may further compromise O&M.     

Assessment of heavy metals by ICP-OES and their impact on insulin stimulating hormone and carbohydrate metabolizing enzymes

Arsenic (As) and cadmium (Cd) have recently emerged as major health concerns owing to their strong association with diabetes mellitus (DM). We aimed to investigate the heavy metals exposure towards incidence of DM at various enzymatic and hormonal levels. Additionally, association of As and Cd with Zinc (Zn, essential metal) was also evaluated. Spot urine samples were collected to assess As, Cd and Zn through ICP-OES. Serum was analyzed by assay method for fasting blood glucose, liver and renal function biomarkers. ELISA was performed to investigate the impact of heavy metals on HbA1c, α-amylase, DPP-IV, IGF-1, leptin, GSH, MDA, SOD, HDL, FFA, TG and interleukin (IL)-6. Association of heavy metals with DM was measured by odds ratio (OR) and level of significance was assessed by Chi-squared test. Unpaired student's t-test was used to compare DM-associated risk factors in heavy metals-exposed and unexposed participants. As and Cd were detectable in 75.4% and 83% participants with mean concentration of 75.5 ppb and 54.5 ppb, respectively. For As exposure, OR in the third quartile was maximum ie 1.34 (95% CI, 0.80 to 2.23), however the result was not statistically significant (P > .05). For Cd exposure, OR in the fourth quartile was considerably high, 1.62 (95% CI, 1.00 to 2.61), with a significant probability value (P < .05). Urinary Cd was negatively associated with Zn. As and Cd exposure increases the incidence of DM in the general population. Impaired hormonal and enzymatic levels in diabetic and non-diabetic exposed participants reflect the multiple organ damage by heavy metal exposure.     

Use of biomimetic microtissue spheroids and specific growth factor supplementation to improve tenocyte differentiation and adaptation to a collagen-based scaffold in vitro

Tenocytes represent a valuable source of cells for the purposes of tendon tissue engineering and regenerative medicine and as such, should possess a high degree of tenogenic differentiation prior to their use in vivo in order to achieve maximal efficacy. In the current report, we identify an efficient means by which to maintain differentiated tenocytes in vitro by employing the hanging drop technique in combination with defined growth media supplements. Equine tenocytes retained a more differentiated state when cultured as scaffold-free microtissue spheroids in low serum-containing medium supplemented with l-ascorbic acid 2-phosphate, insulin and transforming growth factor (TGF)-β1. This was made evident by significant increases in the expression levels of pro-tenogenic markers collagen type I (COL1A2), collagen type III (COL3A1), scleraxis (SCX) and tenomodulin (TNMD), as well as by enhanced levels of collagen type I and tenomodulin protein. Furthermore, tenocytes cultured under these conditions demonstrated a typical spindle-like morphology and when embedded in collagen gels, became highly aligned with respect to the orientation of the collagen structure following their migration out from the microtissue spheroids. Our findings therefore provide evidence to support the use of a biomimetic microtissue approach to culturing tenocytes and that in combination with the defined growth media described, can improve their differentiation status and functional repopulation of collagen matrix.     

Disparate exposure to physically demanding working conditions in France

BackgroundOur study was aimed at examining disparate exposure to physically demanding working conditions in France, a key objective being to identify the types of employees/jobs requiring high-priority preventive actions.MethodsWe analyzed the data from the 2017 French nationwide cross-sectional survey (SUMER) on occupational hazards to which French employees in various sectors were subjected. The prevalence of several types of physically demanding working conditions (lifting of heavy loads, awkward body postures, vibrations, noise, and extreme temperatures) was explored. Potential associations of individual and job characteristics with these factors of hardship at work were studied by multivariate logistic regression.ResultsIn total, 48% of employees were exposed to at least one physically demanding working condition and 24.8% were exposed to multiple constraints. While managers and intellectual professionals were exposed relatively infrequently to physical constraints, blue-collar workers experienced the highest frequency of exposure. On the one hand, the role of company size depended on the factor of hardship at work considered; on the other hand, employees in large-scale companies were generally less exposed. As expected, employees in the construction industry were the most exposed to physical constraints; that said, our results also show that some activities in the services sector (e.g., personal care, administrative and support services) were quite significantly affected by a wide array of physically demanding working conditions.ConclusionNotwithstanding the establishment in France of Plans de Santé au travail (preventive workplace health and safety plans), occupational risks were found to be high, and above all, they were unevenly distributed among the various socio-professional categories, and strongly contributed to social inequalities in health. Our results identify the types of publics to be designated as high-priority targets for preventive measures aimed at reducing the adverse impacts of physically demanding working conditions and the incidence of associated musculoskeletal disorders.