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Background: Schistosomiasis is a parasitic disease that is endemic in 78 countries and affects almost 240 million people worldwide. It has been acknowledged that an integrated approach that goes beyond drug treatment is needed to achieve control and eventual elimination of the disease. Improving hygiene has been encouraged by World Health Assembly, and one aspect of good hygiene is using soap during water-contact activities, such as bathing and doing laundry. This hygiene practice might directly reduce the skin exposure to cercariae at transmission sites. A systematic review was carried out to investigate the efficacy of soap against schistosome cercariae and to identify the knowledge gaps surrounding this topic. Methodology: Six online databases were searched between 5th and 8th July of 2021. Records returned from these databases were screened to remove duplicates, and the remaining records were classified by reading titles, abstracts, and full texts to identify the included studies. The results were categorised into two groups based on two different protective mechanisms of soap (namely, damage to cercariae and protection of skin). Conclusions: Limited research has been conducted on the efficacy of soap against schistosome cercariae and only 11 studies met the criteria to be included in this review. The review demonstrates that soap has the potential of protecting people against schistosome cercariae and there are two protective aspects: (1) soap affects cercariae adversely; (2) soap on the skin prevents cercariae from penetrating the skin, developing into adult worms and producing eggs. Both aspects of protection were influenced by many factors, but the differences in the reported experimental conditions, such as the cercarial endpoint measurement used and the cercaria numbers used per water sample, lead to low comparability between the previous studies. This review indicates that more evidence is needed to inform hygiene advice for people living in schistosomiasis endemic areas. Author summary: Schistosomiasis affects millions of people living in low- and middle-income countries lacking safe access to water, sanitation and hygiene (WASH). Infection occurs through skin-contact with water containing schistosome cercariae which are released from the snail intermediate hosts. The disease is mainly controlled through drug treatment with praziquantel in humans, but reinfection is possible if contact with cercaria-contaminated water continues. Despite all the efforts that have been made, this disease remains a major public health problem in disease-endemic regions. The use of soap during water contact, as part of good hygiene practice, may be an effective complementary control method as it might reduce the penetration of schistosome cercariae into the skin, thereby reducing the likelihood of reinfection. We conducted a systematic review to summarise previous research into the efficacy of soap against schistosome cercariae, and to identify current knowledge gaps to inform future studies. The information gathered from this review can provide policymakers with preliminary scientific evidence (e.g. the soap types, soap amounts, exposure times that are needed) to further emphasise the importance of effective soap usage in reducing the spread of schistosomiasis. [ABSTRACT FROM AUTHOR]

The study area is situated in Shouguang City, Shandong Province, as the largest greenhouse vegetable production base in Northern China. Samples of facility agricultural soil, open-field agricultural soil, and agricultural plastic mulch film were collected to investigate the distribution characteristics, influencing factors, and discharging sources of microplastics (MPs). Microplastic abundance of three soil layers at all sampling sites ranged from 310 to 5698 items/kg, with an average value of 1444 ± 986 items/kg. The main size category of MPs was less than 0.5 mm, and the contribution of MPs with sizes <0.5 mm in the 10–25 cm layer of facility agricultural soils was significantly higher (p < 0.05) than that in the 0–5 cm soil layer, which indicated that small MPs tended to migrate to deeper soil layers. The prevailing shapes of MPs were fragment and film, while polypropylene, ethylene-propylene copolymer, and polyethylene dominated among chemical compositions. The fractions of silty and sandy particles were correlated with the abundance of MPs, and the microplastic abundance in sandy loam was significantly higher (p < 0.05) than that in silty loam or loam based on the international classification standard. Thus, the soil texture may affect the distribution of MPs in local agricultural soils. In addition, the planting age of facility agricultural soil was related to microplastic abundance, while there was no significant difference in the microplastic abundances of facility agricultural soils under different irrigation methods. The microplastic abundance in sandy loam surpassed that in silty loam or loam, small size (<0.5 mm) MPs tended to migrate to deeper soil layers, and planting age affected microplastic abundance in facility agricultural soils. Unlabelled Image • Particles with sizes less than 0.5 mm dominated the size distribution of MPs in agricultural soils. • Smaller MPs (<0.5 mm) tended to migrate to deeper layers of agricultural soils. • The most frequent shapes of MPs in agricultural soils were fragment and film. • Soil texture and planting age of facility agriculture may affect the distribution of MPs in agricultural soils. [ABSTRACT FROM AUTHOR]

Microplastics pollution in river systems has generated great concern; however, few studies have focused on the contributions of multiple influencing factors to microplastics in river systems. In the current study, we utilized data on microplastics in surface sediments from the Haihe River, a seagoing river in northern China to establish a generalized additive model (GAM) for quantifying the effects of multiple factors on the distribution of microplastics. A high abundance of microplastics (4980 ± 2462 items∙kg−1 dry weight) was found. Small particles (< 1000 µm) accounted for a dominant proportion (44.8−61.0%). Polyethylene (PE) was the chief component with an averaged fraction of 49.3%, in which low- and high-density polyethylene contributed 90.7% and 9.3% of the PE, respectively. Microplastics abundance was positively correlated with sediment TOC and the silt fraction (p < 0.05) but negatively correlated with the sand fraction (p < 0.05). The GAM could explain approximate 60% of the total microplastics abundance, and dam (28.5%), sediment TOC (22.9%), and sewage effluent (17.6%) were the main contributors to total variations in microplastics abundance. Local sewage effluent acted as an important point source of microplastics discharge, and the dam on the river greatly affected the deposition and accumulation of microplastics. ga1 • High volumes of microplastics exist in surface sediments. • Fragments of transparent and white LDPE contribute dominant components. • There are strong correlations between microplastics abundance and both TOC and grain size in surface sediments. • The contributions of multiple influencing factors to microplastics in sediments are quantified. • Sewage effluent and dam are primarily responsible for distribution of microplastics in surface sediments. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs), the most commonly produced and used plasticizers, are widely used in plastic products and agroecosystems, posing risks to agricultural products and human health. However, current research on PAE pollution characteristics in agricultural soils in China is not comprehensive; affecting factors and relationships with microplastics and plasticizer organophosphate esters have not been sufficiently considered. In this study, farmland soil samples were collected with field questionnaires on a national scale across mainland China. The results showed that the detection rate of PAEs was 100% and the Σ 16 PAEs concentrations were 23.5 - 903 μg/kg. The level of PAEs was highest in the greenhouse, and significantly higher than that in mulched farmland (p < 0.05). The PAE concentration in northwestern China was the lowest among different physical geographic zones. PAEs in farmlands posed a low cancer risk to Chinese people. PAE pollution in farmlands was significantly (p < 0.05) affected by agronomic measures (such as disposal method), environmental factors, and socioeconomic factors. Overall, PAEs were significantly and positively correlated (p < 0.05) with organophosphate esters but not with microplastics. This study aims to provide scientific data for relevant prevention and control policies, as well as actionable recommendations for pollution reduction. [Display omitted] • The phthalate ester (PAE) concentration was highest in greenhouses on different agricultural lands. • The farmland in northwestern China was the least contaminated by PAEs. • PAEs in farmland soils pose a low cancer risk to Chinese people. • The disposal method prominently affected PAE pollution in farmland soils. • PAEs may not indicate microplastics in farmland soils within huge regions. [ABSTRACT FROM AUTHOR]

The distribution, partitioning behavior and risk assessment of phthalate esters (PAEs) in the surface sediment-pore water system of the Haihe River were investigated. The total cumulative concentrations of 21 PAE species (Σ 21 PAEs) in the surface sediment ranged from 45.9 to 1474.1 ng·g−1 dry weight (dw) and were from 17.9 to 2628.8 ng·mL−1 in the pore water. Di (2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), and diisobutyl phthalate (DIBP) were the dominant components, and their sum accounted, on average, for 88.4% and 72.0% of Σ 21 PAEs in the surface sediment and pore water, respectively. The spatial distributions of Σ 21 PAEs in the surface sediment and pore water indicated that large amounts of the consumed products contained plasticizers in the urban and nearshore areas and increased the discharge of PAEs into the Haihe River. The river dam also affected PAEs distributions. The organic carbon normalized partitioning coefficient (log K OC) followed a sequence as dry season (2.47 ± 0.35 mL·g−1) > wet season (2.02 ± 0.45 mL·g−1) > normal season (1.98 ± 0.42 mL·g−1). The risk quotient (RQ) method was employed to assess the potential ecological risk from specific species. High ecological risks of DEHP to the sensitive algae, crustacean, and fish species along with high ecological risks of DIBP to sensitive fish species were found in the surface sediment and pore water for all sampling seasons. In addition, DBP in the surface sediment and pore water exhibited moderate and high ecological risks to sensitive aquatic species. The highest RQ values for PAEs were found in the surface sediment and pore water in suburban and urban areas, respectively, and indicated that anthropogenic activities may cause severe river pollution and high risk to the local aquatic ecosystem. High levels and ecological risks from PAEs were found in the urban river, and the partitioning behaviors of PAEs between the surface sediment and pore water were not significantly affected by their hydrophobicity, especially for species with low K OW. Unlabelled Image • DEHP, DBP, and DIBP were the dominant species in surface sediment and pore water. • Notable differences in PAEs concentrations were observed between urban reaches and nonurban reaches. • Partitioning of PAEs between surface sediment and pore water was not significantly affected by K OW. • DEHP and DIBP in surface sediment exhibited high ecological risk. • DEHP, DIBP, and DBP in pore water showed high ecological risk. [ABSTRACT FROM AUTHOR]

Atmospheric PM 10 (particulate matter with aerodynamic diameter <10 μm) samples were collected in the cities along the Bohai Sea Rim during heating and non-heating periods, and ionic per - and polyfluoroalkyl species (PFASs) in the PM 10 were measured. The total concentration of ionic PFASs ranged from 21.8 to 87.0 pg/m3, and the mean concentration of ionic PFASs during the day (42.6 pg/m3) was slightly higher than that at night (35.1 pg/m3). Generally, diurnal variations in the levels of ionic PFASs were consistent with those in the PM 10 concentrations. Perfluorooctanoic acid (PFOA, 23.5–33.7%), perfluoropentanoic acid (PFPeA, 28.3–39.9%) and perfluorobutyric acid (PFBA, 17.1–20.1%) accounted for the dominant compositional contributions. Significant positive correlations (p < 0.05) between the main components of PFASs and O 3 implied that oxidative degradation (O 3 served as the main oxidant) in the period of non-heating may affect the short-chain PFASs. The clustering analysis of a 72-h backward trajectory indicated that cross-provincial transport contributed to ionic PFASs at the sampling sites. Compared with ingestion via daily diet, the inhalation of PM 10 exhibited an insignificant contribution to the estimated average daily intakes (ADI s) of PFASs by different age groups. In addition, the calculated hazard ratios (HR s) for the non-cancer respiratory risk, based on the air concentrations of PFOA and perfluorooctane sulfonate (PFOS), also manifested lower non-cancer risk through inhalation exposure. The effects of heating and non-heating activity and diurnal variation on the concentrations of PFASs, dominated by PFOA, PFPeA, and PFBA in PM 10 , were determined, and atmospheric trans-provincial input served as an important source. Unlabelled Image • Heating activity and diurnal variation affected the levels of PFASs in PM 10. • PFOA, PFPeA and PFBA were determined to be the dominant species. • Backward trajectory indicated fluorine chemical plant as a main source of PFASs. • No strong health risks by inhalation exposure to PFOA and PFOS were estimated. [ABSTRACT FROM AUTHOR]