Association of childhood rhinitis with phthalate acid esters in household dust in Shanghai residences.

OBJECTIVE: Phthalate acid esters (PAEs) have been identified to be associated with children's health. Present study was conducted to assess associations between PAEs in household dust and childhood rhinitis. METHODS: Based on phase II of CCHH study (China, Children, Home, Health) conducted in Shanghai, China, 266 indoor dust samples were collected from participants' families. Concentrations of PAEs in dust samples were measured by chemical treatment and gas chromatograph-mass spectrometer. Information about individuals and residences was surveyed by questionnaires. Logistic regression models were applied to obtain the associations between PAEs and childhood rhinitis. RESULTS: Higher concentrations of benzyl butyl phthalate (BBP) were found in those families with children who had diagnosed rhinitis. Significantly higher concentrations of bis(2-ethylhexyl) phthalate (DEHP) and PAEs with high molecular weight (HMW-PAEs) were found in the positive group of lifetime rhinitis. Using the multiple and ordinal logistic regression models adjusted by covariates, dibutyl phthalate (DBP), DEHP, and HMW-PAEs were found to be significantly associated with diagnosed rhinitis. Boys who exposure to higher concentrations of DBP, DEHP, HMW-PAEs, and total PAEs have significant associations with diagnosed rhinitis compared with girls who exposure to lower concentration of PAEs. CONCLUSIONS: Present observational study indicated that exposure to high concentrations of DBP, DEHP, and HMW-PAEs in house settled dust was a risk factor for rhinitis for children, especially for boys.

Associations between phthalic acid esters in household dust and childhood asthma in Shanghai, China.

Phthalic acid esters (PAEs) have a negative impact on human health and are widely distributed in China. As part of the China, Children, Home, Health (CCHH) study, we investigated the associations between childhood asthmatic symptoms and PAEs in settled house dust in Shanghai, China. We found that di-2-ethylhexyl phthalate (DEHP), dibutyl phthalate (DBP), and diisobutyl phthalate (DiBP) were abundant in the indoor environment. A total of 27 % of children suffered from diagnosed asthma. The Mann-Whitney U test and multiple logistic regression were used to obtain the associations between PAEs and childhood asthmatic symptoms. Stratification analysis was performed to reveal the influence of gender on the associations between PAE exposure and target symptoms. Compared with low concentrations of PAEs, high concentrations of high molecular weight PAEs (HMW-PAEs) were significantly associated with childhood diagnosed asthma (adjusted odds ratios (AORs) > 1, P < 0.05). Moreover, significantly negative associations were found between high concentrations of DiBP and current cough (AORs<1, P < 0.05). All significantly positive associations were observed among girls, and most of the associations of dimethyl phthalate (DMP) and diethyl phthalate (DEP) exposure with the studied symptoms among girls were higher than those among boys. Exposure to PAEs may be a risk factor for asthmatic symptoms in children, especially in girls.

[Indoor Formaldehyde and Benzene Series in Shanghai Residences and Their Associations with Building Characteristics and Lifestyle Behaviors].

From March 2013 to December 2014, we on-site inspected indoor concentrations of formaldehyde and a benzene series in 454 children's bedrooms that were decorated earlier than one year before our inspection. Large differences existed in the formaldehyde and benzene-series concentrations among individual bedrooms. Bedrooms that were inspected in winter had significantly higher concentration of formaldehyde than bedrooms that were inspected in other seasons (P<0.001), but the benzene-series concentration had no significant seasonal difference. Among bedrooms that were inspected in spring, those using different materials as wall coverings had significant differences in concentrations of the benzene series. Among bedrooms that were inspected in summer, those using different materials as floor coverings had significant differences in concentrations of the benzene series (P<0.01). Among bedrooms that were inspected in autumn, those with>5 household bonsais had significantly higher concentrations of formaldehyde than other bedrooms did. Among bedrooms that were inspected in winter, those with frequent use of air humidifiers and those in which pets were kept had significantly higher concentrations of the benzene series than other bedrooms did (P<0.05). These results indicate that, after a long time since decoration, the types of household wall and floor covering materials still have certain relationships with indoor benzene-series levels and, compared to decoration materials, household ventilation perhaps has greater effect on indoor formaldehyde levels. The indoor benzene-series level perhaps has associations with indoor humidity level and the keeping of pets in households. Household bonsaies may have limited effect on indoor formaldehyde and benzene-series levels in residences that were decorated a long time ago.

Associations of urinary phthalate metabolites with residential characteristics, lifestyles, and dietary habits among young children in Shanghai, China.

Exposure to household phthalates has been reported to have adverse effects on children's health. In this paper, we used phthalate metabolites in the first morning urine as indicators of household phthalate exposures and examined their associations with residential characteristics, lifestyles and dietary habits among young children. During 2013-2014, we collected morning urines from children aged 5-10years in Shanghai, China and obtained the related information about analyzed factors in this study by questionnaires. Urinary phthalate metabolites were analyzed by isotope dilution-high performance liquid chromatography (HPLC)-heated electrospray ionization source (HESI) coupled with a triple quadrupole mass spectrometry. ANOVA, the Mann-Whitney or Kruskai-Wallis rank tests, and multivariate linear regression analyses were used to examine the target associations. Ten metabolites of seven phthalates in 434 urine samples were analyzed. The detection rates of eight metabolites (MiBP, MnBP, MEHP, MECPP, MEHHP, MEOHP, MEP, and MMP) were >90%, except for MBzP (51.2%), and MCHP with <10.0% of detection rate was not included in analyses. By multivariate linear regression analyses, factors significantly associated with higher concentrations of metabolites included non-usage household air cleaners (MEP and MEHP), changing the child's pillowcase less than one time a week (DEHP metabolites), dusting furniture in the child's bedroom less than three times a week (MMP and MnBP), using more plastic toys (DEHP metabolites and MEP), often having soft drinks (DEHP metabolites) and candies (MiBP). Our results indicated that phthalate exposures were common among Shanghai children and residential characteristics had less significant associations with urinary phthalate metabolites compared with lifestyles and dietary habits. Using less plastic toys, having less candies and soft drinks, using household air cleaner, as well as frequently changing the child's pillowcase and dusting furniture in the child's bedroom could reduce phthalate exposures among children.

Household indoor air quality and its associations with childhood asthma in Shanghai, China: On-site inspected methods and preliminary results.

Few studies were conducted for associations of home environment with childhood health by on-site inspection in China. During 2013-2014, we conducted a case-control study with home inspection among 454 children (186 asthma children and 268 non-asthma children) in Shanghai, China. In this paper, we detailedly described the inspected methods and analyzed the preliminarily collected data. Except in winter, most residences meet the national standard for indoor temperature and relative humidity. Most living rooms had ≤1000ppm CO2, whereas over half of the child's bedrooms had slightly >1000ppm CO2 during night. Most residences had notably lower than 2500cfu/m3 airborne culturable fungi and ≤100µg/m3 formaldehyde. More than 70% of the child's bedrooms had ≤75µg/m3 PM2.5 and ≤150µg/m3 PM10. Indoor and outdoor concentrations of particulate matters had strong linear correlations (r=0.891-0.922; p-value <0.001). Most differences between cases and controls were not significant with respect to CO2, culturable fungi, formaldehyde, and particulate matters. Before and after adjusted for potential confounders, indoor averaged concentration of CO2 and particulate matters generally had negative associations with childhood history of doctor-diagnosed asthma in spring, summer, and autumn. Only in winter, indoor CO2 concentration was significantly associated with the increased odds of childhood asthma. Our results indicated that air quality among most residences in Shanghai could meet the national standard for indoor air quality in warm seasons; but household air quality and ventilation status in winter should be greatly improved. We suspected that those "unexpected" negative associations could exist due to changes in lifestyle behaviors regarding indoor air quality after the child being diagnosed asthma by a doctor.

Note: A charge sensitive spectroscopy amplifier for position sensitive micro-channel plate detectors.

A compact and low noise charge sensitive spectroscopy amplifier which can be integrated into position sensitive micro-channel plate (MCP) detectors has been constructed. The amplifier was optimized by using a wave form generator and tested by a chevron shape MCP detector. The output noise of 4 mV(rms) was achieved while the gain is 10(12) V/C and the shaping time is 700 ns.

Note: A timing micro-channel plate detector with backside fast preamplifier.

A timing micro-channel plate detector with a backside double-channel fast preamplifier was developed to avoid distortion during signal propagation from the anode to the preamplifier. The mechanical and electronic structure is described. The detector including its backside preamplifier is tested by a (241)Am α-source and a rise time of ~2 ns with an output background noise of 4 mV(rms) was achieved.