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Highlights • Seasonal associations of urinary phthalate and sex hormone levels were found. • Diet and exercise were associated with sex hormones levels. • Exercise, red meat and urinary phthalates exhibited additive effect on hormones. Abstract Phthalate can affect sex hormones secretion. Exercise and diet habits affect sex hormones levels. However, interaction of phthalates exposure and diet or exercise habits with sex hormones is unclear. We enrolled 106 residents aged 11–88 years (48 males and 58 females) from two communities, Wuhan city, China during the winter of 2014 and summer of 2015. Data were collected on socio-demographic characteristics and lifestyle by a questionnaire in two seasons. Participants provided the blood and urine samples over 3 consecutive days for measuring sex hormones and urinary phthalate metabolites. We assessed the associations of urinary phthalate metabolites levels, lifestyle with hormones levels, the interaction of phthalate exposure and lifestyle with hormones levels using multivariate binary logistic regression models. High urinary mono-(2-ethyl-5-oxyhexyl) phthalate (MEOHP) levels and no exercise had an additive interaction on abnormal serum progesterone (PROG) levels in winter as well as on abnormal serum follicle-stimulating hormone (FSH) or luteinizing hormone (LH) levels in summer. High urinary MEOHP levels and red meat intake (>1 time/day) had an additive interaction with abnormal levels of serum FSH only in the winter. Phthalates exposure may confer differential susceptibility to abnormal hormones levels in individuals with no exercise or eating meat >1 time/day. [ABSTRACT FROM AUTHOR]

This study investigated the formation of toxic iodinated trihalomethanes (I-THMs) during breakpoint chlorination of iodide-containing water. Impact factors including I − concentration, natural organic matter (NOM) concentration and type, pH as well as Br − /I − molar ratio were systematically investigated. Moreover, the incorporation of I − into I-THM formation was also calculated. The results showed that I-THM formation varied in different zones of the breakpoint curves. I-THMs increased with increasing chlorine dosage to breakpoint value and then dropped significantly beyond it. Iodoform (CHI 3 ) and chlorodiiodomethane (CHClI 2 ) were the major I-THMs in the pre-breakpoint zone, while dichloroiodomethane (CHCl 2 I) was the dominant one in the post-breakpoint zone. The formation of I-THMs increased remarkably with I − and dissolved organic carbon (DOC) concentrations. More bromine-containing species were formed as Br − /I − molar ratio increased from 0.5 to 5. In addition, the major I-THM compound shifted from CHCl 2 I to the more toxic CHClBrI. As pH increased from 6.0 to 8.0, I-THM formation kept increasing in the pre-breakpoint zone and the speciation of I-THMs changed alongside the breakpoint curves. The incorporation of I − during breakpoint chlorination was highly dependent on chlorine, I − , and NOM concentrations, NOM type, solution pH and Br − /I − molar ratio. [ABSTRACT FROM AUTHOR]

Chlorine dioxide (ClO 2) has emerged as a broad-spectrum, safe, and effective disinfectant due to its high oxidation efficiency and reduced formation of organochlorinated by-products during application. This article provides an updated overview of ClO 2 -based oxidation processes used in water treatment. A systematic review of scientific information and experimental data on ClO 2 -based water purification procedures is presented. Concerning ClO 2 -based oxidation derivative problems, the pros and cons of ClO 2 -based combined processes are assessed and disinfection by-product (DBP) control approaches are proposed. The kinetic and mechanistic data on ClO 2 reactivity towards micropollutants are discussed. ClO 2 selectively reacts with electron-rich moieties (anilines, phenols, olefins, and amines) and eliminates certain inorganic ions and microorganisms with high efficiency. The formation of chlorite and chlorate during the oxidation process is a crucial concern when utilizing ClO 2. Future applications include the combination of ClO 2 with ferrous ions, activated carbon, ozone, UV, visible light, or persulfate processes. The combined process can reduce by-product generation while still ensuring ClO 2 sterilization and disinfection. Overall, this research could provide useful information and new insights into the application of ClO 2 -based technologies. [Display omitted] • ClO 2 application derivative problems and DBPs control methods are discussed. • UV/ClO 2 process can achieve high-efficiency disinfection and reuse ClO 2 -. • The mechanistic information on combination process based on ClO 2 is analyzed. • The pros and cons of ClO 2 -based treatments are evaluated. • Challenges and perspectives for future development are proposed. [ABSTRACT FROM AUTHOR]

Iodinated trihalomethanes (I-THMs) have drawn increasing concerns due to their higher toxicity than those of their chlorinated and brominated analogues. In this study, I-THM formation was firstly evaluated for three treatment scenarios - (i) chlorine alone, (ii) chloramine alone, and (iii) mixed chlorine/chloramine - in the presence and absence of UV irradiation for the iodide-containing humic acid solution or natural water. The results indicated that I-THM formation decreased in the order of mixed chlorination/chloramination > chloramination > > chlorination, which fitted the trend of toxicity evaluation results using Chinese hamster ovary cells. Conversely, total organic halide concentration decreased in the order of chlorination > > chloramination ≈ mixed chlorination/chloramination. Besides, I-THM formation can be efficiently controlled in a UV-activated mixed chlorine/chloramine system. Influencing factors including pH values and Br-/I- molar ratios were also systematically investigated in a mixed chlorine/chloramine system. Enhanced I-THM formation was observed with increasing pH values (6.0–8.0) and Br-/I- molar ratios (1: 1–10: 1). The results obtained in this study can provide new insights into the increasing risk of I-THM formation in a mixed chlorine/chloramine system and the effective control of I-THMs in the iodide-containing water using UV irradiation. [Display omitted] • I-THM concentration decreased in the processes of mixed chlorine/chloramine > chloramine >> chlorine. • UV irradiation exerted efficient control of I-THM formation in a mixed chlorine/chloramine system. • TOX and CHO cell toxicity can be significantly reduced in a UV-activated mixed chlorine/chloramine system. • Both pH values and Br-/I- molar ratios presented vital influence on I-THM formation in a mixed chlorine/chloramine system. [ABSTRACT FROM AUTHOR]

Abstract: This study shows that iodinated disinfection by-products (I-DBPs) including iodoform (IF), iodoacetic acid (IAA) and triiodoacetic acid (TIAA) can be produced when iodide-containing waters are in contact with potassium permanganate. IF was found as the major I-DBP species during the oxidation. Iodide was oxidized to HOI, I2 and I3 −, consequently, which led to the formation of iodinated organic compounds. I-DBPs varied with reaction time, solution pH, initial concentrations of iodide and potassium permanganate. Yields of IF, IAA and TIAA increased with reaction time and considerable I-DBPs were formed within 12h. Peak IF yields were found at circumneutral pH range. However, formation of IAA and TIAA was favored under acidic conditions. Molar ratio of iodide to potassium permanganate showed significant influence on formation of IF, IAA and TIAA. The formation of IF, IAA and TIAA also depended on the characteristics of the waters. [Copyright &y& Elsevier]

Abstract: The chemical oxidation of the herbicide ametryn was investigated by aqueous chlorination between pH 4 and 10 at a temperature of 25°C. Ametryn was found to react very rapidly with aqueous chlorine. The reaction kinetics can be well described by a second-order kinetic model. The apparent second-order rate constants are greater than 5×102 M−1 s−1 under acidic and neutral conditions. The reaction proceeds much more slowly under alkaline conditions. The predominant reactions were found to be the reactions of HOCl with neutral ametryn and the charged ametryn, with rate constants equal to 7.22×102 and 1.58×103 M−1 s−1, respectively. The ametryn degradation rate increases with addition of bromide and decreases with addition of ammonia during the chlorination process. Based on elementary chemical reactions, a kinetic model of ametryn degradation by chlorination in the presence of bromide or ammonia ion was also developed. By employing this model, we estimate that the rate constants for the reactions of HOBr with neutral ametryn and charged ametryn were 9.07×103 and 3.54×106 M−1 s−1, respectively. These values are 10- to 103-fold higher than those of HOCl, suggesting that the presence of bromine species during chlorination could significantly accelerate ametryn degradation. [Copyright &y& Elsevier]

In recent years, ultraviolet (UV) irradiation coupled with chlor(am)ination process is ubiquitous in secondary water supply systems in many cities of China. However, the disinfection by-products (DBPs) formation in a UV-activated mixed chlorine/chloramine system (MCCS) still remains unclear. In this study, the DBPs formation in a UV-activated MCCS was systematically investigated, considering influencing factors including the mass ratios of free chlorine to NH 2 Cl, UV irradiation, pH values, NOM types, Br− concentration and toxicity of the DBPs. Results indicated that DBPs formation decreased remarkably as mass ratio of free chlorine to NH 2 Cl changed from 5:0 to 0:5. The DBPs formation in humic acid (HA)-containing water was the highest, followed by those in fulvic acid (FA) and algal organic matter (AOM). Besides, better control of the DBP-related calculated toxicity can be achieved in acidic conditions regardless of the UV irradiation. Furthermore, in the presence of Br−, a significant reduction of DBPs formation could be achieved in a UV-activated MCCS. The findings also demonstrated that DBPs formation in real water can be effectively reduced at high UV fluence in a MCCS. ga1 • Mass ratio of HOCl/NH 2 Cl and UV irradiation significantly affected DBPs formation. • UV-activated MCC process reduced DBPs formation in alkaline conditions. • UV irradiation could control DBPs formation in Br−-containing water during MCC process. • MCC process achieved DBPs control in real water at high UV fluence. [ABSTRACT FROM AUTHOR]

• ZnO-NPs exposed in lactation damage blood-milk barrier and enter into breast milk. • ZnO-NP-triggered ROS generation and MKK4/JNK activation induce cell junction damage. • JNK activation directly phosphorylates β-catenin, thus damaging adherens junction. • JNK activates PIAS-1 and induces SUMOylation of ZO-1, thus damaging tight junction. Zinc oxide nanoparticles (ZnO-NPs) have been extensively applied in our daily life. Humans are at high risk of being exposed to ZnO-NPs, which induce potentially adverse health effects. Although a growing number of studies have investigated the toxic effects of ZnO-NPs, the available data concerning ZnO-NP interactions with the blood-milk barrier (BMB) remain highly limited. Herein, we systematically investigated the damage to BMB integrity induced by ZnO-NPs and the mechanisms involved. ZnO-NPs that were intravenously injected into lactating dams accumulated in the mammary gland and entered into the breast milk, inducing disruption to BMB integrity and changes in the tight junction (TJ) and adherens junction (AJ) components. Furthermore, using an in vitro BMB model composed of EpH4-Ev cells, we verified that ZnO-NP-triggered ROS generation and the activation of MKK4 and JNK are the main mechanism of cell-cell junction damage. More interestingly, JNK activation played different roles in inducing changes in the TJ and AJ complex, and these effects did not need to activate the downstream c-Jun. These data provide more information for understanding ZnO-NP interactions with the BMB and raise concern for the daily use and the intravenous use of ZnO-NPs by lactating mothers. [ABSTRACT FROM AUTHOR]

• Associations of bisphenol exposure with child neurodevelopment were assessed. • The higher BPS levels were associated with lower PDI scores in boys, but not girls. • Second-trimester BPA concentrations were inversely associated with MDI scores. • Prenatal BPF exposure was not significantly associated with child neurodevelopment. While increasing evidence has shown that prenatal bisphenol A (BPA) exposure is adversely associated with child neurodevelopment, little is known about the neurodevelopmental effects of BPA alternatives, such as bisphenol S (BPS) and bisphenol F (BPF). We aimed to evaluate the relationships of repeated measurements of bisphenol exposure during pregnancy with child neurodevelopment. From 2014–2015, 456 mother-child pairs were included in the present study. Each had a spot urine sample in the first, second, and third trimester, respectively, during pregnancy for BPA, BPS, and BPF measurements. Children's neurodevelopment was assessed using the Bayley Scales of Infant Development at 2 years. In adjusted models, children's psychomotor development index scores decreased across quartiles of BPS concentrations [-5.52 (95 % CI: -10.06, -0.99) in the 4th quartile vs. 1 st quartile, P -trend = 0.01]. Each 10-fold increase in BPA concentrations was related to lower mental development index scores only in the second trimester [-2.87 (95 % CI: -4.98, -0.75), P trimester-int = 0.04]. However, prenatal BPF exposure was not significantly associated with child neurodevelopment. We provide evidence that prenatal exposure to BPA and BPS may affect child neurodevelopment. [ABSTRACT FROM AUTHOR]

• The mixture of eight OH-PAHs had an overall effect on telomere length or lung function. • Phthalate metabolites mixture counteracted the overall effect of OH-PAHs mixture on FEV1. • Phthalate metabolites mixture counteracted the overall effect of OH-PAHs mixture on FVC. • Urinary 2 + 3−OHPhe was the most important contributor to decrease in FEV1, FVC or RTL. • Urinary MEHP enhanced an overall effect of PAHs exposure on FEV1 or FVC reduction. Exposure to polycyclic aromatic hydrocarbons and phthalates are linked to lung function decline and altered relative telomere length (RTL) accompanying with oxidative stress and inflammatory events in human body. However, limited data are available about impacts of co-exposure of PAHs and phthalates on lung function and RTL. We conducted a pilot study with repeated measures during the winter of 2014 and summer of 2015 in Wuhan city, China. Participants took part in the measures of lung function, RTL, urinary monohydroxylated-PAHs (OH-PAHs) and phthalate metabolites over three consecutive days in each season. Linear mixed-effect (LME) models and Bayesian kernel machine regression (BKMR) were used to analyze the relations of OH-PAHs or phthalate metabolites with lung function or RTL. LME models showed the negative associations of 3-day average of hydroxyphenanthrene (2 + 3-, 4−OHPhe) or 1-hydroxypyrene with FEV1, 3-day average of 2 + 3−OHPhe with FVC. BKMR models revealed the negative relation of eight OH-PAHs with FEV1, FVC or RTL; nine phthalate metabolites may counteract an overall effect of eight OH-PAHs on FEV1, FVC or RTL. The findings indicated that urinary phthalate metabolites may counteract the negative association of urinary OH-PAHs on FEV1 or FVC, which may be partially linked to shorter RTL regarding biological aging. [ABSTRACT FROM AUTHOR]

• This study first compared different disinfection processes for controlling DBPs in rainwater. • The application of chloramine could control the yields of C-DBPs, but not N-DBPs in rainwater. • K 2 FeO 4 exerted effective control of most identified DBPs in rainwater. • UV-related AOPs could control DBP formation as well as cyto- and genotoxicity. • UV/PS was more effective to reduce DOC and alter DOM in rainwater than UV/H 2 O 2. With increasing shortage of clean water, rainwater has been considered as a precious alternative drinking water source. The processes applied to rainwater treatment are responsible for the safety of drinking water. Therefore, we systematically compared different disinfection processes to evaluate the control of disinfection by-product (DBP) formation and integrated cyto- and genotoxicity of the treated rainwater for the first time. The evaluated disinfection processes included chlorination and chloramination, pre-oxidation by potassium permanganate (KMnO 4) and potassium ferrate (K 2 FeO 4), ultraviolet/hydrogen peroxide (UV/H 2 O 2), and ultraviolet/persulfate (UV/PS) processes. The results revealed that chloramination was effective for controlling the formation of carbonaceous DBPs (C-DBPs), but not nitrogenous DBPs (N-DBPs). Compared to KMnO 4 pre-oxidation, better reduction of almost all DBPs was observed during K 2 FeO 4 pre-oxidation. According to the calculation of cytotoxicity index (CTI) and genotoxicity index (GTI), cyto- and genotoxicity of the samples decreased obviously at the dosage of ≥ 2.0 mg/L KMnO 4 and K 2 FeO 4. The control of the cyto- and genotoxicity of the formed DBPs from the two UV-related AOPs was more effective at the dosage of ≥ 1.0 mM PS and ≥ 5.0 mM H 2 O 2. Moreover, UV/PS was much more powerful to alter the structure of DBP precursors in rainwater. [ABSTRACT FROM AUTHOR]