Journal of Environmental Health Science and Engineering

In this study, the parameters influencing p-cresol removal efficiency in soil washing method were investigated. Primarily, extraction efficiencies of three Tween series surfactants (Tween 20, Tween 60, Tween 80) with 10 mM concentration were compared. Tween 80 showed the best results since its value (55%) was 4% and 13% higher than that of Tween 60 and Tween 20. The impact of mixed surfactant on extraction rate was examined by employing a mixture of Tween 80 and one anionic surfactant (sodium dodecyl sulfate) with different molar ratio as the main washing solution. The results denoted that the molar ratio of 3:2 (SDS:Tween80) could enhance the extraction rate up to 38% compared to using SDS and Tween 80 alone. Regarding the initial p-cresol concentration in the collected sample, the cleanup level (390 mg/kg) could only be achieved using the mixed-surfactant. Thus, the minimum required surfactant concentrations to hit the target level was calculated to be 3.54 g/L of Tween 80 and 2.105 g/L of SDS (molar ratio of 0.27 SDS:Tween80). Studying the role of surfactant concentration indicated that its increment from 10 mM to 20 mM, which is way above all the reagents’ critical micelle concentration (CMC), does not affect the removal rate considerably. The same results were obtained comparing the effect of washing time in three different levels (30 min, 60 min and 90 min). However, temperature showed to be a more significant parameter as it could enhance the results up to 20% (for SDS).

Fluoride level, due to its narrow therapeutical range, must be constantly monitored in beverages, especially in daily-consumed plant infusions. Fluoride is important for prevention of tooth decay and osteoporosis, but its excess leads to fluorosis. Since tea can selectively absorb fluorides from soils, the question arises if a long-term consumption can pose an adverse effect on human health. Infusions of 33 popular teas (black, green, white, earl grey, pu-erh), tea-like products (rooibos, yerba mate) and herbs (chamomile, mint, nettle, purges, yarrow) available in the Polish market were analyzed with respect to a fluoride level by means of a validated ion-selective electrode method, which is proven to be fast and reliable. Significantly different fluoride concentrations in infusions were observed, with black tea on top, where extraction of fluoride is the highest (average 2.65 mg F−/L, range 0.718–6.029 mg/L). Two-fold higher fluoride contents were measured in infusions made from black tea bags than from leaves (average 3.398 mg/L and 1.529 mg/L, respectively). Green teas released comparable amounts of fluoride as black teas, while in herbal extracts the fluoride content was negligible. The rank with respect to the fluoride concentration in an infusion is as follows: black tea > green tea > earl grey > pu-erh > white tea>>>rooibos, yerba mate, herbal products. Increasing of brewing time results in an increased fluoride content, but the overall content of fluoride in the analyzed infusions of teas and herbs was not high enough to cause a risk of fluorosis, even if left to brew up to 15 min.

Abstract Background Discharging the oily wastewater in the environment causes serious problems, because of the oil compounds and organic materials presence. Applying biological methods using the lipase enzyme producer microorganisms can be an appropriate choice for treatment of these wastewaters. The aim of this study is to treat those oil wastewaters having high concentration of oil by applying lipase enzyme producer bacteria. Materials and methods Oil concentration measurement was conducted using the standard method of gravimetric and the wastewater under study was synthetically made and contained olive, canola and sunflower oil. The strain used in this study was Pseudomonas strain isolated from compost fertilizer. The oil under study had concentration of 1.5 to 22 g/l. Results The oil removal amount in concentrations lower than 8.4 g/l was over 95 ± 1.5%. Increase of the oil's concentration to 22 g/l decreases the amount of removal in retention time of 44 hours to 85 ± 2.5%. The best yield of removing this strain in retention time of 44 hours and temperature of 30°C was achieved using Ammonium Nitrate as the nitrogen resource which yield was about 95 percent. Conclusion The findings of the research showed that Pseudomonas bacteria isolated from the compost fertilizer can degrade high concentration oils.

The present study aimed at demonstrating the heat stress situation (distribution and intensity) based on a standard and common heat stress index, Wet Bulb Globe Temperature (WBGT), during hot seasons and interpret the obtained results considering global warming and rising temperature in different parts of the country based on climate changes studied in Iran. Heat stress assessment was done using WBGT index. Environmental parameters were measured simultaneously in the early, middle and end of shift work. The personal parameters including cloth thermal insulation and metabolic rate of 242 participants from 9 climatic categories were recorded for estimating effective WBGT (measured WBGT plus cloth adjustment factor as well as metabolic rate effect). The values of the indicator were categorized in the statistical software media and then linked to the climatic zoning of the data in the GIS information layers, in which, WBGT values relating to selected stations were given generalization to similar climatic regionalization. The obtained results showed that in the summer about 60 % and more than 75 % of the measurements relating to 12 pm and 3 pm, respectively, were in heat stress situations (i.e. the average amount of heat stress index was higher than 28 °C). These values were found to be about 20–25 % in the spring. Moreover, only in the early hours of shift work in spring could safe conditions be seen throughout the country. This situation gradually decreased in the middle of the day hours and was replaced by the warning status and stress. And finally, in the final hours of shift work thermal stresses reached their peaks. These conditions for the summer were worse. Regarding several studies related to climate change in Iran and the results of present study, heat stress, especially in the central and southern parts of Iran, can be exacerbated in the decades to come if climate change and rising temperature occurs. Therefore, paying attention to this critical issue and adopting macro-management policies and programs in the field of workplace health is essential.

A self-efficacy instrument should be condition-specific. There are several instruments for measuring self-efficacy, but none are air pollution-specific. This study aimed to develop a self-efficacy measure for assessing pregnant women’s responses to air pollution hazards. A random sample of pregnant women aged between 18 and 35 years attending three prenatal care centers were entered into the study. Prenatal care centers randomly selected from a list of centers located in different geographical regions of Tehran, Iran. After careful consideration and performing content and face validity, a 4-item measure was developed and participants completed the questionnaire. Reliability was estimated using internal consistency and validity was assessed by performing confirmatory factor analysis (CFA) and known group comparison. In all 200 eligible pregnant women were studied. The mean age of participants was 26.9 (SD = 4.8) years and it was 27.9 (SD = 9.1) weeks for gestational age. The findings showed almost perfect results for both content validity ratio (CVR = 1) and content validity index (CVI = 1). The confirmatory factor analysis indicated a good fit to the data, and known group comparison revealed satisfying results. Internal consistency as measured by the Cronbach’s alpha coefficient was found to be 0.74. In general, the findings suggest that this new generated scale is a reliable and valid specific measure of self-efficacy in response to air pollution hazards for pregnant women. However, further studies are needed to establish stronger psychometric properties for the questionnaire.

This is the first published assessment on agricultural pesticide use in Iran with the aim to identify pesticide products with a potential of causing acute or chronic hazard to human health. It also establishes a baseline for future comparisons and for trend assessments. The amounts of imported technical materials for formulation by local manufacturers as well as imported final product formulations were extracted from the registration data of the Plant Protection Organization of Iran in 2012–2014. The hazard indicators used were acute oral toxicity and chronic toxicity. For the latter, carcinogenicity, mutagenicity, and adverse effects on reproduction or development (CMR toxicity), and low Acceptable Daily Intake (ADI) were used. The comparative potential of the active ingredients of concern in terms of chronic toxicity was assessed using the average annual volume of their estimated use divided by their respective ADI, called chronic hazard potential (CHP) in the present text. The contribution of individual pesticides in different use categories to the total CHP of the user category, was also calculated, using the average annual volume of the active ingredients of all pesticides used during the period 2012-2014. On average about 14,000 tonnes of agriculture pesticides, expressed in active ingredients (AI), were annually used in Iran. Herbicides constituted the largest volume (43%), followed by insecticides and acaricides (37%) and fungicides (19%). 0.1% and 47% of the formulated products met the criteria of WHO Class Ib (highly hazardous) and Class II (moderately hazardous) products respectively. Aluminium phosphide and magnesium phosphide were identified as products of primary concern and chlorpyrifos, diazinon and paraquat as products of secondary concern, in terms of their acute human health hazard. No compound in carcinogenicity category 1A or 1B or germ cell mutagenicity/reproduction toxicity category 1A was identified. Six compounds (diazinon, chlorpyrifos, dichlorvos, metam sodium, paraquat and dimethoate) were identified as products with chronic hazard potential based on a low ADI. The assessment identified and prioritized agriculture pesticide used in Iran in terms of their acute and chronic hazard to human health for re-registration scheme recently established by PPO and for risk mitigation. It also set priority for research into development of alternative products and practices to minimize pesticide risks. Chronic hazard potential - amount of use adjusted with toxicity may serve as a useful point of reference for trend analysis also in the use of less hazardous agricultural pesticide products.

The biosorption of heavy metals Hg(II) and Cu(II) from aquatic solution by biomass of dried Sargassum fusiforme was studied in the paper. The Sargassum fusiforme was able to absorb appreciable amount of mercury and copper from the aquatic solutions within 60 min of contact time with the metal solution and exhibited high removal of mercury and copper at low equilibrium concentrations. The specific adsorption of both Hg(II) and Cu(II) increased at low concentration of biomass and decreased when biomass concentration exceeded 2.0 g/L. The binding of mercury followed Freundlich model while copper supported Langmuir isotherm for adsorption with their r2 values of 0.971 and 0.923, respectively. The maximum adsorption per unit masses of Sargassum fusiforme (mg/L) at equilibrium (qmax) for Hg(II) and Cu(II) were calculated to be 30.86 and 7.69 mg/g, respectively. The biosorption by Sargassum fusiforme was best described using a pseudo-second-order kinetic model for copper and mercury ions in solution in the study. The adsorption was pH dependent as the maximum mercury biosorption and copper adsorption was happened at solution pH of 8–10.