Ultra violet filters in the urine of preschool children and drinking water

Exposure to benzophenones during pregnancy and the influence of socioeconomic, lifestyle, and environmental factors on exposure levels

Endocrine-disrupting chemicals (EDCs) have emerged as significant environmental pollutants. Benzophenones (BPs), a group of EDCs, are widely used and suspected of interfering with human health from early development to later life stages. This study assessed urinary concentrations of selected BPs, including 2,4-dihydroxy benzophenone (BP-1), 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-OH-BP), and 2,2'-dihydroxy-4-methoxy benzophenone (BP-8), in 166 pregnant women from the PERSIAN cohort in Isfahan, Iran, during the first trimester. The study also examined the associations between maternal BP levels and socioeconomic, lifestyle, and environmental factors. BP-1 and BP-3 were detected in all samples, followed by 4-OH-BP (98 %) and BP-8 (95 %). Among the BP metabolites, the highest level belonged to BP-3 with a median concentration of 7.50 μg/g Creatinine (Cr) and the lowest was assigned to BP-8 amounting to 1.32 μg/g Cr. Multivariate regression analysis indicated that food consumption behaviour and storage methods, physical activity, and education level were significantly correlated with urinary 4-OH-BP concentrations (p ≤ 0.5). BP-3 levels were positively associated with personal care product (PCP) use, food consumption habits, physical activity, and income. BP-1 was linked to food consumption habits and PCP usage, while BP-8 was associated with household cleaning product (HCP) use and income level. These findings suggest that demographic, socioeconomic, lifestyle and environmental factors influence maternal BP exposure in early pregnancy, potentially affecting foetal development. Further research is needed to confirm these effects. Regulatory measures should be considered to minimize BP exposure, particularly among pregnant women.

Implementation of Sensitive Method for Determination of Benzophenone and Camphor UV Filters in Human Urine

The level of the human body's burden of benzophenone and camphor ultraviolet (UV) filters can be estimated from their urinary levels. The present study describes the implementations and validation of the sensitive analytical method for the analysis of seven benzophenone and two camphor UV filters in urine. Sample preparation includes overnight enzymatic hydrolysis and ethyl acetate extraction followed by purification by dispersive solid-phase extraction using a sorbent Z-Sep. For the analysis, ultra-high performance liquid chromatography coupled with tandem mass spectrometry was used. Validation was performed using a Standard Reference Material® 3673 and an artificially contaminated urine sample. Target analyte recoveries ranged from 79-113% with repeatability expressed as a relative standard deviation of 2-15%. The limits of quantification were between 0.001 and 0.100 ng/mL in urine. This method was subsequently applied to examine the urine samples collected from Czech women. The analytes benzophenone-1 and 4-hydroxy-benzophenone were the most common analytes present in 100% of the samples, whereas benzophenone-3 was quantified in only 90% of the urine samples. The other four determined benzophenone derivatives were quantified in ≤33% of the samples. The derivatives of camphor were not detected in any samples. This method could be applied in biomonitoring studies.

Distribution, sources, ecological and human health risks of organic ultraviolet filters in coastal waters and beach deposits in Hainan, China

Organic ultraviolet filters (OUVFs) are extensively incorporated into both cosmetic items and industrial products and have been commonly found in water ecosystems. This study aims to examine the environmental levels, sources, ecological and human health risks of 14 commonly used OUVFs both in coastal water and beach deposit samples collected from the nearshore regions of Hainan Island and the South China Sea. This is first study highlighting the contamination of OUVFs in Hainan Island and utilizing economic and tourism data to confirm the potential source of OUVF pollution in costal aquatic and coastal ecosystem. Along the coastal tourist regions of Hainan Island, the median concentrations in coastal waters and beach deposits of these OUVFs fall within the range from 1.2 to 53.2 ng/L and 0.2-17.0 ng/g dw, respectively. In coastal water and beach deposit, the concentration of BP-3 was the highest, with median concentrations of 53.2 ng/L and 17.0 ng/g dw, respectively. Regarding human health risks, the daily intake of all 14 OUVFs through swimming was found to be 40-48 ng/kg/day. Ecological risk assessment indicates that BP-3 presents a medium risk for marine microalgae with a concurrent low risk for corals. The correlation analysis underscores a substantial interrelation of OUVFs in both coastal waters and beach deposits with various economic indicators, including annual rainfall, overnight tourists, total hotel rooms (unit), room occupancy rate, and sewage treatment capacity.

Human exposure risk of organic UV filters: A comprehensive analysis based on primary exposure pathways

The exposure of organic UV filters has been increasingly confirmed to induce adverse effects on humans. However, the critical exposure pathway and the vulnerable population of organic UV filters are not clearly identified. This paper attempts to evaluate the health risk of commonly used organic UV filters from various exposure routes based on comprehensive analysis strategy. The estimated daily intakes (EDI) and hazard quotient (HQ) values of organic UV filters through four pathways (dermal exposure, indoor dust, indoor air, and drinking water) for various age groups were determined. Although the total HQ values (0.01-0.4) from comprehensive exposure of organic UV filters were below risk threshold (1.0), infants were identified as the most vulnerable population, with EDI (75.71 ng/kg-bw/day) of 2-3 times higher than that of adults. Additionally, the total EDI values of individual exposure pathways were estimated and ranked as follows: indoor air (138.44 ng/kg-bw/day) > sunscreen application (37.2 ng/kg-bw/day) > drinking water (21.87 ng/kg-bw/day) > indoor dust (9.24 ng/kg-bw/day). Moreover, we successfully tailored the Sankey diagram to depict the EDI proportion of individual organic UV filters from four exposure pathways. It was noted that EHMC (ethylhexyl methoxycinnamate) and EHS (ethylhexyl salicylate) dominated the contribution of EDI (72 %) via indoor air exposure routes. This study serves as a crucial reference for enhancing public health risk awareness concerning organic UV filters, with a special focus on the vulnerable populations such as infants and children.

Relationship between the use of hair products and urine benzophenone-3: the Korean National Environmental Health Survey (KoNEHS) cycle 4

Background

Benzophenone-3 is a type of ketone with 2 benzene rings attached to a carbonyl group (C=O) and one benzene ring attached to a hydroxyl group (-OH). As an endocrine-disrupting chemical, benzophenone-3 is known to be associated with reproductive, developmental, thyroid, and endocrine toxicities. Benzophenone-3 is commonly used in hair products, cosmetics, and ultraviolet (UV) filters because of its characteristic property to absorb UV light. This study aims to investigate the association between the use of hair products and urine benzophenone-3 using the data from the Korean National Environmental Health Survey (KoNEHS) cycle 4 (2018-2020), which represents the Korean population.

Methods

Using the KoNEHS cycle 4 survey, the data of 3,796 adults aged ≥ 19 years were analyzed. Based on the 75th percentile concentration of urine benzophenone-3, the participants were divided into the low- and high-concentration groups. Chi-square test was conducted to analyze the association of urine benzophenone-3 with distribution of general characteristics, use of personal care products, consumption of marine foods, and use of plastic products as the variable. Logistic regression analysis was conducted to calculate odds ratios (ORs) for the high-concentration group of urine benzophenone-3 based on the use of hair products.

Results

Women with < 6 times or ≥ 6 times of hair product usage had significantly higher adjusted ORs compared to those who did not use hair products. The calculated ORs were 1.24 (95% confidence interval [CI]: 1.12-1.38) for women with < 6 times of usage and 1.54 (95% CI: 1.33-1.79) for women with ≥ 6 times of usage.

Conclusions

This study revealed the association between the use of hair products and the concentration of urine benzophenone-3 in the general Korean population.

An evaluation of dogs' exposure to benzophenones through hair sample analysis

Introduction

Benzophenones (BPs) are used in various branches of industry as ultraviolet radiation filters, but they pollute the natural environment, penetrate living organisms, and disrupt endocrine balance. Knowledge of the exposure of domestic animals to these substances is extremely scant. The aim of the study was to investigate long-term exposure of companion dogs to BPs and relate this to environmental factors.

Material and Methods

Hair samples taken from 50 dogs and 50 bitches from under 2 to over 10 years old were analysed for BP content with liquid chromatography-tandem mass spectrometry.

Results

The results revealed that dogs are most often exposed to 2-hydroxy-4-methoxybenzophenone (BP-3) and 4-dihydroxybenzophenone (BP-1). Concentration levels of BP-3 above the method quantification limit (MQL) were noted in 100% of the samples and fluctuated from 4.75 ng/g to 1,765 ng/g. In turn, concentration levels of BP-1 above the MQL were noted in 37% of the samples and ranged from <0.50 ng/g to 666 ng/g. Various factors (such as the use of hygiene and care products and the dog's diet) were found to affect BP concentration levels. Higher levels of BP-3 were observed in castrated/spayed animals and in animals that required veterinary intervention more often.

Conclusion

The results obtained show that the analysis of hair samples may be a useful matrix for biomonitoring BPs in dogs, and that these substances may be toxic to them.

UV filters in everyday cosmetic products, a comparative study

Today, UV filters are found as contaminants in a variety of biological fluids and environment, e.g. in vegetable crops and surface water. This is because UV filters are widely used in everyday products. In this context, we focused this study on cosmetic products, in order to assess the importance of this source of contamination. The study of 742 cosmetic products, excluding actual sunscreen products, but including hygiene, personal care and make-up products and perfumes revealed that the most common UV filters present are butyl methoxydibenzoylmethane (90 products or 12.1% of products tested), octyl methoxycinnamate (75 products or 10.1% of products tested), octocrylene (62 products or 8.3% of products tested), octyl salicylate (43 products or 5.8% of products tested) and titanium dioxide (33 products or 4.4% of products tested). Very few UV filters are found in the hygiene products (only in 12 shampoos/conditioners and in 2 shower gels) and deodorants and toothpastes are completely free of them. Conversely, make-up and perfumes are frequently formulated with at least one UV filter. Seventy-five of the two hundred and forty-four (or 30.7%) skincare products studied contained at least one UV filter. 49.1 of the makeup products studied and 74.3% of perfumes contained it.

The associations between high-levels of urine benzophenone-type UV filters (BPs) and changes in serum lipid concentrations

Little is known about the potential health impacts of benzophenone-type UV filters (BPs) exposure among the general population. In our study conducted in Wuxi, China, we investigated the associations between the concentrations of eight BP-derivatives and five target lipid molecules. We collected basic information, serum, and urine samples from 120 residents aged 9 to 80 in Wuxi. We determined BPs in urine samples and lipid levels in serum samples. Generalized linear models were used to evaluate the differences in ln-transformed serum target lipids levels (μg/L) with different urine BPs quartiles compared to the lowest quartile. Benzophenone-4 (BP-4) had the highest detection rate (95.0%) and geometric mean concentration (1.96 μg/L) among all the BP-derivatives in our study population. The exposure levels of BPs were generally higher in females than in males. Participants in the 9-17 and 18-50 age groups exhibited greater levels of exposure to BPs than those in the 51-80 age group. We observed statistically significant changes in LysoPC (18:0), LysoPE (18:0), ΣLPL, and ΣTL concentrations between the highest and lowest quartiles of BP-4. Similar changes were found in LysoPE (18:0) concentration between the highest and lowest quartiles of ΣBP-3 and ΣBPs. High urine BP concentrations were associated with variations in our target serum lipids involved in neurological and metabolic disorders, and posed a potential health risk. Future studies are warranted to further validate and elucidate our findings.

Exploring environmental obesogenous effects of organic ultraviolet filters on children from a case-control study

It has been globally recognized that obesity has become a major public health concern, especially childhood obesity. There is limited information, however, regarding the exposure risk of organic ultraviolet (UV) filters, a kind of emerging contaminant, on childhood obesity. This study would be made on 284 obese and 220 non-obese Chinese children with eight organic UV filters at urinary levels. The eight organic UV filters, including 2-Ethylhexyl 4-aminobenzoate (PABA-E), octisalate (EHS), homosalate (HMS), 2-Ethylhexyl-p-methoxycinnamate (EHMC), benzophenone-3 (BP-3), amiloxate (IAMC), octocrylene (OC) and 4-Methylbenzylidene camphor (4-MBC) were identified in urine samples with detection rates ranged from 35.32% to 100%, among which PABA-E, HMS, IAMC and OC were firstly detected in children' s urine. And the urinary UV filters concentration was associated with genders, living sites, guardian education levels, household income, and dietary factors. Urinary EHMC concentrations and childhood obesity were positively associated for girls [Adjusted OR = 2.642 (95% CI: 1.019, 6.853)], while OC concentrations and childhood obesity were negatively associated for girls [Adjusted OR = 0.022 (95% CI: 0.001, 0.817)]. The results suggest that EHMC exposure may be an environmental obesogen for girls. Moreover, two statistical models were used separately to evaluate the impact of UV filter mixtures on childhood obesity, including the Bayesian kernel machine regression (BKMR) model and the quantile g-computation (qgcomp) model. The negative association between UV filter mixtures and childhood obesity was proposed from both BKMR and qgcomp models. Further experimental and epidemiological studies are called upon to discern the individual and mixture impacts of organic UV filters on childhood obesity.

Contaminants of emerging concern in urine: a review of analytical methods for determining diisocyanates, benzotriazoles, benzothiazoles, 4-methylbenzylidene camphor, isothiazolinones, fragrances, and non-phthalate plasticizers

Human biomonitoring (HBM) frameworks assess human exposure to hazardous chemicals. In this review, we discuss and summarize sample preparation procedures and analytical methodology for six groups of chemicals of emerging concern (CECs), namely diisocyanates, benzotriazoles, benzothiazoles, 4-methylbenzylidene camphor, isothiazolinones, fragrances, and non-phthalate plasticizers, which are increasingly detected in urine, however, are not yet widely included in HBM schemes, despite posing a risk to human health. The sample preparation procedures depend largely on the chemical group; however, solid-phase extraction (SPE) is most often used due to the minimized sample handling, lower sample volume, and generally achieving lower limits of quantification (LOQs) compared to other extraction techniques. In terms of sample analysis, LC-based methods generally achieve lower limits of quantification (LOQs) compared to GC-based methods for the selected six groups of chemicals owing to their broader chemical coverage. In conclusion, since these chemicals are expected to be more frequently included in future HBM studies, it becomes evident that there is a pressing need for rigorous quality assurance programs to ensure better comparability of data. These programs should include the reporting of measurement uncertainty and facilitate inter-laboratory comparisons among the reporting laboratories. In addition, high-resolution mass spectrometry should be more commonly employed to enhance the specificity and selectivity of the applied analytical methodology since it is underrepresented in HBM. Furthermore, due to the scarcity of data on the levels of these CECs in urine, large population HBM studies are necessary to gain a deeper understanding of the associated risks.

Safety of benzophenone-type UV filters: A mini review focusing on carcinogenicity, reproductive and developmental toxicity

Consumer products containing benzophenone-type ultraviolet (UV) filters (BPs) have been widely accepted by the public, resulting in the widely existence of various BPs in the human body and environment. In recent years, more and more evidences show that BPs are endocrine disruptors. In view of the continuous exposure risk of BPs and their endocrine disrupting characteristics, the carcinogenicity of BPs and their effects on reproduction and development are of particular concern. However, due to the wide varieties of BPs and the scattered toxicity studies on BPs, people have a limited understanding on the safety of BPs. Therefore, this paper systematically reviews the carcinogenicity, reproductive and developmental toxicity of BPs in order to expand people's knowledge on the health risks of BPs and screen for more safe BPs. Although existing toxicological studies are insufficient, it can be determined that BPs have different potentials for carcinogenicity, and reproductive and developmental toxicity. Among those BPs, 2-hydroxyl-4-methoxyl benzophenone needs to be used with caution due to its adverse effects on cancer cell proliferation and migration, reproductive ability, sex differentiation, neurodevelopment, and so on. It is worth noting that functional group substitutions significantly affect the interaction between BPs and biomolecules such as DNA, cancer cells, and seminal fluid, resulting in different levels of toxicity. In short, it is very necessary to evaluate the carcinogenicity, reproductive and developmental toxicity of BPs, which is of great significance for establishing reasonable BPs content standards in cosmetics, water quality treatment standards for BPs, and so on.

The binding mechanism of benzophenone-type UV filters and human serum albumin: The role of site, number, and type of functional group substitutions

Benzophenone-type UV filters (BPs) are common in natural aquatic environments. They can cause endocrine disruption or other adverse effects once they enter the human body via the food chain or drinking water. The primary cause of BPs accumulation and toxicity is the transport of BPs into the human body. Functional group substitutions can have a significant impact on the interactions of BPs and transporters, resulting in a variety of impact effects. Therefore, we explored the interaction between human serum albumin (HSA, a typical transporter) and ten typical BPs [benzophenone (BP1), 2-hydroxybenzophenone (BP2), 4-hydroxybenzophenone (BP3), 2,2'-dihydroxybenzophenone (BP4), 2,4-dihydroxybenzophenone (BP5), 4,4'-dihydroxybenzophenone (BP6), 2,4,4'-trihydroxybenzophenone (BP7), 2,2',4,4'-tetrahydroxybenzophenone (BP8), 2-hydroxy-4-methoxybenzophenone (BP9), and 2,2'-dihydroxy-4-methoxybenzophenone (BP10)] to study the role of functional group substitutions in binding. The results showed that BPs could bind to HSA at site 2, with binding constants ranging from 2.01 × 10³ to 4.57 × 10⁵ L/mol. Compared to BP1, hydroxyl and methoxy substitutions enhanced the BPs-HSA binding. The combined effect of the number and site of hydroxyl substitution at BPs determined the binding strength between BPs and HSA. It was more accessible to bind HSA when BPs were substituted with para-hydroxyl (4-hydroxyl) groups than with ortho-hydroxyl (2-hydroxyl) groups. Moreover, the additional para-methoxy (4-methoxy) group increased the BP-HSA binding strength by approximately 47 times under the same hydroxyl substitution conditions. Theoretical calculations revealed that functional group substitutions increased the intermolecular binding force by increasing the negative electrostatic potential surface area of BPs, which significantly increased the electrostatic and dispersion forces between the BPs and HSA. This BPs-HSA binding decreased the α-helix of HSA and influenced the ratio of other secondary structures, including β-sheet, β-turn, and random coil of HSA. This study provides a theoretical and experimental foundation for understanding the human health risks associated with BPs.

Mixed exposure to phthalates and organic UV filters affects Children's pubertal development in a gender-specific manner

BACKGROUND

Previous studies showed phthalates and UV filters are endocrine-disruptive and associated with puberty. However, few studies have examined effects of mixed exposure.

METHODS

Six phthalate metabolites and 12 organic UV filters were detected among 223 school-age children. Puberty development was evaluated at baseline and after 18 months of follow-up. Ordered logistic regression models, least absolute shrinkage and selection operator (LASSO) regression and quantile-based g-computation (qgcomp) were used to evaluate relationships between phthalate metabolites or UV filters exposure and pubertal development.

RESULTS

Six phthalate metabolites and 5 UV filters were detectable in urine samples. In boys, BP-3 and 4'-MAP were negatively associated with genital (ORBP-3 = 0.52, (0.27, 0.93), OR4'-MAP = 0.45, (0.25, 0.74)) and pubic hair development (ORBP-3:0.24, (0.05, 0.76), OR4'-MAP:0.24, (0.05, 0.77)). In girls, MEP levels were associated with advanced breast development (OR: 1.29, (1.04, 1.64)). LASSO regression identified BP-3, 4'-MAP, and OD-PABA for inverse associations with pubertal development in boys. MEP was related to an increase in girls' breast development (OR: 1.64, (1.08, 2.63)). Overall mixture was related to a 70% reduction in boys' genital development stage, with a larger effect size than a single chemical in qgcomp. Mixed exposure was associated with girls' earlier puberty onset (OR: 2.61, (1.06, 6.42)).

CONCLUSIONS

Our results suggested higher levels of phthalate metabolites and UV filters were associated with delayed pubertal development in boys but with earlier puberty in girls. Higher effect size of joint exposure than single chemicals suggested phthalates and UV filters might have synergistic effects on puberty and distort adolescent endocrine function together.

Concentrations, Compound Profiles, and Possible Sources of Organic UV Filters in Human Milk in China

Ultraviolet (UV) filters are of great concern due to their wide occurrence, bioaccumulation, and toxicity. Little is known about human exposure to UV filters. A total of 3467 individual human milk samples from 24 Chinese provinces were collected during 2017-2019. The concentrations of 12 UV filters in 100 pooled milk samples were determined. The total UV filter concentration was 78-846 (mean 235 ± 120) ng/g lipid weight. The highest and lowest total mean concentrations were for samples from Qinghai and Sichuan provinces, respectively. A significant positive correlation was found between UV radiation levels and UV concentrations in the samples. The dominant UV filters were 2-(2-hydroxy-5-methylphenyl) benzotriazole (UV-P) and ethylhexyl methoxycinnamate (EHMC), which contributed means of 32 and 22%, respectively, to the total concentrations. Plastic products and sunscreens were probably the sources of UV-P and EHMC in the human milk from China, respectively. The mean 2-(3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole (UV-328) concentration was 2.6 ± 2.6 ng/g lipid weight. The UV filter profiles were similar to profiles for samples from Japan, the Philippines, and Switzerland but not for samples from Korea and Vietnam. The estimated daily UV filter intake for breastfed infants was below the corresponding reference dose. This was the first large-scale study of UV filters in human milk and will help assess the risks posed.

Assessment of human exposure to benzophenone-type UV filters: A review

To avoid the harmful effects of UV radiation, benzophenone-type UV filters (BPs) are widely used in personal care products and other synthetic products. Biomonitoring studies have shown the presence of BPs in various human biological samples, raising health concerns. However, there is a paucity of data on the global human exposure to this group of contaminants. In this study, we compiled data on the body burden of BPs along with the possible exposure routes and biotransformation pathways. BPs can easily penetrate the skin barrier and thus, they can be absorbed through the skin. In the human body, BPs can undergo Phase I (mainly demethylation and hydroxylation) and Phase II (mainly glucuronidation and sulfation) biotransformations. From a total of 158 studies, most of the studies are related to urine (concentration up to 92.7 mg L^-1), followed by those reported in blood (up to 0.9 mg L^-1) and milk (up to 0.8 mg L^-1). Among BPs, benzophenone-1 and benzophenone-3 are the most commonly detected congeners. The body burden of BPs is associated with various factors, including the country of residence, lifestyle, income, education level, and ethnicity. The presence of BPs in maternal urine (up to 1.1 mg L^-1), placenta (up to 9.8 ng g^-1), and amniotic fluid (up to 15.7 μg L^-1) suggests potential risks of prenatal exposure. In addition, transplacental transfer of BPs is possible, as demonstrated by their presence in maternal serum and cord serum. The possible association of BPs exposure and health effects was discussed. Future human biomonitoring studies and studies on the potential health effects are warranted. Overall, this review provides a summary of the global human exposure to BPs and can serve as supporting evidence to guide usage in order to protect humans from being exposed to BPs.

Urinary benzophenones and synthetic progestin in Chinese adults and children: concentration, source and exposure

The endocrine-disrupting activities of UV filters and synthetic progestin have raised concerns about their adverse risks. In this study, 208 urine samples were collected from Shanghai residents for the determination of seven benzophenones (BPs) and six synthetic progestins. The highest median concentration (6.21ng g-1 Cr) was observed in young adults (21-50 years), followed by a concentration of 3.86 ng g-1 Cr in elderly adults (over 50 years old), and the lowest median concentration (1.32 ng g-1 Cr) was found in children (8-11 years old). The detection rates of BP-3 and EE2 in adults were 97% and 82%, and in children were 31% and 24%, respectively. Synthetic progestin levels in Shanghai, China, were relatively low compared to other countries. And the urinary BPs level showed an increasing trend in Chinese in the past 5 years. The principal component analysis suggested that adults' exposure to BP-1 and BP-3 was related, which occurs through food or dermal absorption of these chemicals present in cosmetic products and coatings. And diet was an important exposure pathway for children exposed to BPs. Despite relatively high levels of synthetic progestin for female and obese, the total estimated daily intake (EDI) was still lower than acceptable daily intake adopted by America. In the Monte-Carlo analysis, the 95th percentile of hazard quotients (HQs) was 0.83, which indicated that potential health risks were appreciated in the studied population.

Fabrication of Cementitious Microfiltration Membrane and Its Catalytic Ozonation for the Removal of Small Molecule Organic Pollutants

In this study, a low-cost cementitious microfiltration membrane (CM) with a catalytic ozone oxidation function for the removal of organic pollutants was fabricated by using cementitious and C-10 μm silica powders at a certain silica–cementitious particle ratio (s/c). The effect of the s/c on the pore size distribution and mechanical strength of the membrane was investigated. The membrane pore size showed a bimodal distribution, and the higher the s/c, the closer the second peak was to the accumulated average particle size of silica. The increase in the s/c led to a decrease in the bending strength of the membrane. The cross-sectional morphology by SEM and crystal structure by XRD of CMs confirmed that a calcium silicate hydrate gel was generated around the silica powder to improve the mechanical strength of the CM. Considering the bending strength and pore size distribution of CMs, s/c = 0.5 was selected as the optimal membrane fabrication condition. The FT-IR results characterizing the surface functional groups of CMs were rich in surface hydroxyl groups with the ability to catalyze ozone oxidation for organic pollutant removal. Six small molecule organic pollutants were selected as model compounds for the efficiency experiments via a CM–ozone coupling process to prove the catalytic property of the CM. The CM has an alkaline buffering effect and can stabilize the initial pH of the solution in the catalytic ozonation process. The reuse experiments of the CM–ozone coupling process demonstrated the broad spectrum of the CM catalytic performance and self-cleaning properties. The results of this study provide the basis and experimental support to expand the practical application of CMs.

The biological activity of the organic UV filter ethylhexyl methoxycinnamate in rainbow trout (Oncorhynchus mykiss)

UV filters are able to enter the aquatic environment and negatively affect non-target organisms. The aim of this study was to evaluate subchronic exposure to ethylhexyl methoxycinnamate (EHMC) in rainbow trout. The tested EHMC concentrations of 6.9 (low), 96.0 (medium) and 395.6 μg/kg (high) were used. The lowest concentration was based on environmentally relevant concentrations. The higher concentrations were chosen as a multiple of the lowest one to determine the dose-response relationship. EHMC was incorporated into feed pellets. The experiment was conducted for six weeks in a semi-static system. Haematological, biochemical and oxidative stress indices were determined at the end of the experiment and supplemented by histological examination. Significant changes were proven at medium and high concentrations of EHMC. Specifically, increases of glucose, lactate and decrease of albumin and total protein in plasma indicate a stress ethology. Moreover, a decrease of plasma cholesterol, triacylglycerols and ammonia were observed even in the experimental group exposed to the lowest concentration of EHMC, perceived as an environmentally relevant concentration. The ferric reducing ability of plasma was decreased in all tested concentrations. Exposure to the highest concentration of EHMC resulted in a decrease in leukocyte counts. Increased activity of glutathione peroxidase in liver was recorded for the medium and the highest concentration of EHMC. The level of the thiobarbituric acid reactive substances in kidney was elevated for the highest concentration. Decrease of the activity of glutathione-S-transferase in gills for medium concentration of EHMC was registered. Histopathological examination revealed massive destruction of hepatic parenchyma at the highest concentration of EHMC. All these results support the finding of a stress load on the fish organism. In summary, although subchronic exposure to EHMC had no effect on behaviour, mortality or feed intake, this exposure resulted in the alteration of saccharide, lipid and protein metabolism and weakened antioxidant capacity.

Improvement of the fabricated and application of aluminosilicate-based microfiltration membrane

Aluminosilicate composite materials are characterized by their low cost, nontoxicity and facilely shaped. Membrane prepared using aluminosilicate composites have the following disadvantages: large mean pore size and low mechanical strength. To address these limitations, flat microfiltration membranes were fabricated using SiO₂ powder and aluminosilicate composite as raw materials. The membrane performance was optimized by regulating the particle size of SiO₂, the ratio of SiO₂ to aluminosilicate composite (s/a), and the type of chemical admixture. The X-ray diffraction results indicated that the crystalline SiO₂ particles were favorable for the preparation of membranes with higher bending strengths. The decreasing particle sizes of SiO₂ (1.33-0.15 μm) decreased the pore size distribution. The bending strength of the membrane reduced with an increase in s/a, while was effectively enhanced by adding dissolved Na₂SiO₃. The optimized inorganic microfiltration membrane could also catalyze ozone to remove 100% of benzophenone-4 with an initial concentration of 10 mg L^-1 within 15 min, and TOC removal by 52.67%. This paper presents a revised method for preparing an inorganic microfiltration membrane, which is an increasingly promising material for water treatment because of its low cost, low energy consumption, and high catalytic performance.

Risks of organic UV filters: a review of environmental and human health concern studies

Organic UV filters are compounds that absorb UV irradiation by their highly conjugated structure. With the developing consciousness over the last century of the skin damage UV radiation can cause, the demand for organic UV filters has risen, for use not only in sunscreens, but also in other personal care products. The massive production and usage of these organic UV filters has resulted in extensive release into the aquatic environment, and thereby making an important group of emerging contaminants. Considering the widespread occurrence of organic UV filters in not only ambient water, but also sediment, soil and even indoor dust, their threats towards the health of living organisms have been a subject of active investigation. In this review article, we present an overall review of existing knowledge on the risks of organic UV filters from the aspects of both environmental and human health impacts. As for the environment, some organic UV filters are proven to bioaccumulate in various kinds of aquatic organisms, and further to have adverse effects on different kinds of animal models. Toxicological studies including in vivo and in vitro studies are important and effective means to ascertain the effects and mechanisms of organic UV filters on both the ecosystem and humans. Subsequent concerns arise that these compounds will affect human health in the long term. This review concludes by suggesting future lines of research based on the remaining knowledge gaps.

Organic UV filter exposure and pubertal development: A prospective follow-up study of urban Chinese adolescents

BACKGROUND

UV filters, widely used in personal care and industrial products, are being found in the environment and, in humans where with limited understanding on their potential health effects, especially during puberty.

OBJECTIVES

To examine the association between UV filter exposure and pubertal development in a prospective follow-up study.

METHODS

This study included 521 elementary and high school students from a suburban area of Shanghai. The initial study was done in October to November 2011; the follow-up study in April to May 2013. Twelve urinary organic UV filters were quantified, and the pubertal development was assessed at each study period by trained physicians using Tanner staging. We used (ordered) logistic regression model and multilevel mixed-effect (ordered) logistic regression model to assess cross-sectional and longitudinal effects between urinary concentration of five major UV filters and pubertal development of stages, onset and pace.

RESULTS

Ethylhexyl methoxycinnamate (EHMC) and its metabolite 4'-methoxyacetophenone (4'-MAP), two benzophenone derivatives (BP-2, BP-3) and Ethylhexyl dimethyl PABA (OD-PABA) were the most extensively detected UV filters in urine with geometric means (95% CI) in 2010 and 2012 as 1.77 (1.599, 1.956) and 2.28 (1.985, 2.622) ng/mL for EHMC; 4.55 (4.219, 4.907) and 5.26 (4.783, 5.775) ng/mL for 4'-MAP; 4.38 (4.011, 4.774) and 5.74 (5.023, 6.562) ng/mL for BP-2; 0.83 (0.760, 0.903) and 1.09 (0.967, 1.220) ng/mL for BP-3; 5.37 (4.949, 5.820) and 5.80 (5.193, 6.486) pg/mL for OD-PABA. Significant trend P-values (P < 0.05) include: EHMC and its metabolite were negatively correlated with stages of testicular volume and genital development; BP-3 was also negatively correlated with stages of testicular volume in boys, while OD-PABA positively correlated with stages of pubic hair and breast development in girls. Also, EHMC was associated with later pubertal onset of pubic hair and testicular volumes in boys, while OD-PABA correlated with earlier pubertal onset of breast development in girls. OD-PABA also significantly speeded up the progression of pubic hair and breast development in girls.

DISCUSSION

UV filters were extensively detected. Exposure to EHMC and BP-3 was significantly associated with later pubertal development in boys, and OD-PABA was associated with earlier pubertal development in girls. It demonstrates that the UV filters so widely used in personal care products and widely detected in environments are finding their way back into people where they are distorting endocrine function of adolescents.