Biomarkers of occupational benzene exposure: A Systematic Review to estimate the exposure levels and individual susceptibility at low doses.

Benzene is associated with diverse occupational and public health hazards. It exhibits an ability to rapidly permeate the skin and contaminate water and food sources, leading to dermal and ingestion exposures. Despite numerous studies examining the associations between benzene and various indicators of harm, the findings have yielded inconsistent results. Furthermore, relying solely on air concentration as a measure of benzene exposure is limited, as it fails to account for internal exposure dose and individual susceptibility. This study aimed to conduct a comprehensive review in order to present current knowledge on benzene biomarkers and their significance in evaluating exposure levels and associated health hazards. The search methodology adhered to the PRISMA guidelines and involved the application of specific inclusion and exclusion criteria across multiple databases including PubMed, Embase, and Web of Science. Two researchers independently extracted and evaluated the relevant data based on predetermined criteria. Following the screening process, a total of 80 articles were considered eligible out of the initially retrieved 1053 articles after undergoing screening and assessment for inclusion. As the level of exposure decreased, specific biomarkers demonstrated a gradual increase in limitations, including heightened background concentrations and vulnerability to confounding factors. The advancement of sampling and analysis techniques will yield new biomarkers. Additionally, when conducting practical work, it is crucial to employ a comprehensive utilization of diverse biomarkers while excluding individual metabolic variations and combined exposure factors.

Formaldehyde Exposure of Aquaculture Workers in Korea.

OBJECTIVES: Korea's aquaculture sector primarily cultivates aquatic life, with fish seed production as a focus. Formalin, a parasiticide, consists of 37% formaldehyde mixed with yellow No. 4 dye. Formaldehyde vaporization poses cancer risks, classified as a carcinogen. Korea regulates formaldehyde as a hazardous substance, requiring workplace environment measurements. Few aquaculture farms have conducted these checks in recent years. In this study, we investigated actual formaldehyde exposure levels among Korean aquaculture workers, highlighting a critical safety concern. METHODS: A field survey was conducted to measure formaldehyde exposure at 10 aquaculture farms in areas where Korean aquaculture is concentrated. Short-term and long-term personal samples, local samples, and direct-reading measurements were conducted. Formaldehyde exposure levels were detected in short-term personal samples from six farms and in long-term personal samples from two farms, and formaldehyde was detected in all local samples. In direct-reading measurements, a high concentration of formaldehyde was sustained for short periods. RESULTS: Long-term (8-hour) personal samples were mostly non-detectable, except for farms A and D, which had levels of 0.0009 ppm and 0.0017 ppm, respectively. Short-term (15-minute) samples were non-detectable in four farms, with an average of 0.0158 (±0.0130) ppm in the remaining six farms. Local samples from all farms had an average of 0.0384 (±0.0957) ppm of formaldehyde. For farms A and D, where long-term sampling detected formaldehyde, real-time measurements showed a sustained high concentration in farm A for about 48 minutes before decreasing. Farm D had no detectable formaldehyde throughout the monitoring period. CONCLUSION: According to the formaldehyde exposure level assessment, short term exposure to formaldehyde during and immediately after application of formalin nearly exceeded the ACGIH TLV STEL in one farm. However, concentration of long term samples appeared at 10% of ACGIH TLV TWA. Additional study is recommended to determine whether exposure to formaldehyde poses a health risk for aquaculture workers during application of formalin.

[A Review of Comparative Studies on Exposure Levels of Air Pollutants Among Different Modes of Transportation in China's Cities].

Urban traffic is closely related to the daily life of the public,and air pollution in the traffic microenvironment has become a public health problem that cannot be ignored.This paper reviews the comparative studies of air pollutant exposure levels among different modes of transportation in multiple cities in China.By comparing the exposure levels of pollutants among different modes of transportation,this paper provides a reference for protecting the health of the public in daily transportation and selecting targeted control measures.

Tacrolimus Drug Exposure Level and Smoking Are Modifiable Risk Factors for Early De Novo Malignancy After Liver Transplantation for Alcohol-Related Liver Disease.

De novo malignancy (DNM) is the primary cause of mortality after liver transplantation (LT) for alcohol-related liver disease (ALD). However, data on risk factors for DNM development after LT are limited, specifically in patients with ALD. Therefore, we retrospectively analyzed all patients transplanted for ALD at our center before October 2016. Patients with a post-LT follow-up of <12 months, DNM within 12 months after LT, patients not on tacrolimus in the 1st year post-LT, and unknown smoking habits were excluded. Tacrolimus drug exposure level (TDEL) was calculated by area under the curve of trough levels in the 1st year post-LT. 174 patients received tacrolimus of which 19 (10.9%) patients developed a DNM between 12 and 60 months post-LT. Multivariate cox regression analysis identified TDEL [HR: 1.710 (1.211-2.414); p = 0.002], age [1.158 (1.076-1.246); p < 0.001], number of pack years pre-LT [HR: 1.021 (1.004-1.038); p = 0.014] and active smoking at LT [HR: 3.056 (1.072-8.715); p = 0.037] as independent risk factors for DNM. Tacrolimus dose minimization in the 1st year after LT and smoking cessation before LT might lower DNM risk in patients transplanted for ALD.

Exposure and risk assessment for agricultural workers during chlorothalonil and flubendiamide treatments in pepper fields.

Pesticides are indispensable tools in modern agriculture for enhancing crop productivity. However, the inherent toxicity of pesticides raises significant concerns regarding human exposure, particularly among agricultural workers. This study investigated the exposure and associated risks of two commonly used pesticides in open-field pepper cultivation, namely, chlorothalonil and flubendiamide, in the Republic of Korea. We used a comprehensive approach, encompassing dermal and inhalation exposure measurements in agricultural workers during two critical scenarios: mixing/loading and application. Results revealed that during mixing/loading, dermal exposure to chlorothalonil was 3.33 mg (0.0002% of the total active ingredient [a.i.]), while flubendiamide exposure amounted to 0.173 mg (0.0001% of the a.i.). Conversely, dermal exposure increased significantly during application to 648 mg (chlorothalonil) and 93.1 mg (flubendiamide), representing 0.037% and 0.065% of the total a.i., respectively. Inhalation exposure was also evident, with chlorothalonil and flubendiamide exposure levels varying across scenarios. Notably, the risk assessment using the Risk Index (RI) indicated acceptable risk of exposure during mixing/loading but raised concerns during application, where all RIs exceeded 1, signifying potential risk. We suggest implementing additional personal protective equipment (PPE) during pesticide application, such as gowns and lower-body PPE, to mitigate these risks.

Effect of vegetable consumption on risk of gastric cancer: a systematic review and multi-level meta-analysis of prospective studies.

Vegetables are known to be beneficial to human health, but the association between vegetable consumption and gastric cancer remains uncertain. To synthesise knowledge about the relationship between vegetable group consumption and gastric cancer risk, update present meta-analyses and estimate associations between vegetable consumption and gastric cancer risk based solely on prospective studies, we perform a PRISMA-compliant three-level meta-analysis. Systematic search identified thirteen prospective studies with fifty-two effect sizes that met all inclusion criteria and no exclusion criteria for our meta-analysis. Pooled risk ratios (RRs) showed a positive association between high vegetable consumption and low gastric cancer risk (pooled RR 0·93, 95% confidence interval 0·90-0·97, P = 0·06). In moderator analyses for indicators of gender, region and quantity of vegetable intake, there was no significant difference between subgroups. However, the effect became significant in populations with lower than the minimum risk exposure level (TMREL) of vegetable consumption (P < 0·05). Higher vegetable intake is associated with a decreased risk of gastric cancer. This effect may be limited to specific populations, such as ones with lower vegetable consumption. Evidence from our study has important public health implications for dietary recommendations.

Surveillance of noise exposure level in industrial enterprises-Jiangsu Province, China, 2022.

Occupational noise exposure is the most prominent problem in industrial enterprises in Jiangsu Province. Since 2019, China has established the National Surveillance System for Occupational Hazards in the workplace to grasp the current occupational hazards in critical industries, including occupational noise. According to the Work Plan for Surveillance of Occupational Hazards in the Workplace (2022) issued by the National Health Commission of the People's Republic of China, the noise exposure level of 3,142 enterprises in our province was monitored, the median and interquartile range (IQR) were calculated, and the distribution of noise exposure level was described by industry classification, enterprise-scale and ownership type of the enterprise. The railway, shipping, aerospace, and other transportation equipment manufacturing industries exhibited the highest proportion (42.9%) of individual noise exposure levels exceeding 85 dB(A), followed by the motor vehicles manufacturing industry (36.4%). The proportion of individual noise exposure levels exceeding 85 dB(A) was higher in medium and small enterprises, with rates of 28.1 and 28.6%, respectively. The highest proportion of personal noise exposure levels exceeding 85 dB(A) was observed in Hong Kong, Macao and Taiwan investment enterprises (37.5%), followed by incorporated companies (34.6%) and limited liability companies (28.1%), the lowest was state-owned enterprises(15.5%). The areas with excessive noise are primarily concentrated in grinding, welding, machining, cutting, and other related operations, accounting for 61.2% of the total. Among these operations, grinding accounts for 29.8%. The highest environmental noise and individual noise intensity were found in sandblasting and grinding positions, with individual noise intensities of 115.5 dB(A) and 108.4 dB(A), respectively. The noise exposure risk is so high that cannot be ignored in the manufacturing industry, especially in Hong Kong, Macao, and Taiwan investment enterprises, incorporated companies and medium and small enterprises.

[Exposure Level and Risk Impact Assessment of Pesticides and Veterinary Drugs in Aquaculture Environment].

To explore the exposure level of pesticides and veterinary drugs in an aquaculture environment and its impact on the ecological environment, this study took the aquaculture environment in Shanghai as an example, and samples of water, sediment, and inputs from 40 major aquaculture farms were collected from July to September 2022. The types and contents of pesticides and veterinary drugs were screened using high-performance liquid chromatography-electrostatic field orbital ion trap mass spectrometry, and the risk quotient (RQ) method was used to assess the ecological risk of pesticide contamination in water and sediment. The results showed that 13 drugs were screened out from 204 samples (72 samples of water, 72 samples of mud, and 60 samples of input), namely, chlorpromazine, carbendazim, thiophanate, diazepam, florfenicol, simazine, amantidine, diazepam, trimethoprim, ciprofloxacin, ofloxacin, mebendazole, and enrofloxacin. Among them, 12 species were found in water samples with concentrations ranging from 0.016 µg·L-1 to 2.084 µg·L-1. The concentrations of seven species in the mud samples ranged from 0.018 µg·kg-1 to 23.101 µg·kg-1. The results showed that there were four types of inputs, ranging from 1.979 µg·kg-1 to 101.940 µg·kg-1. Seven drugs were found in both water and sediment. The risk quotient (RQ) results showed that there were some high and middle risks in both water and sediment samples of aquaculture farms, and the ecological risks of carbendazim were the highest in both water and sediment samples of aquaculture farms; the RQ values were 3.848 and 1.580, respectively, indicating high risk. It is suggested to strengthen the control and management of exogenous pesticides and veterinary drugs in aquaculture environments to protect the ecosystem health of the aquaculture environment.

Concentrations and sociodemographic determinants of per- and polyfluoroalkyl substances in women pregnant using assisted reproduction technology in comparison with women pregnant naturally / 环境与职业医学

Background Per- and polyfuoroalkyl substances (PFAS) are categorized as persistent organic pollutants and commonly detected in humans, and their toxicity has attracted widespread attention. However, few studies have reported comparison of PFAS levels and potential factors between women pregnant using assisted reproduction technology (ART) and women pregnant naturally. Objective To analyze and compare serum concentrations and sociodemographic determinants of PFAS in pregnant women conceiving through ART and conceiving naturally from Shanghai. Methods Based on the China National Birth Cohort (CNBC) in Shanghai from 2017 to 2019, 333 pregnant women conceiving through ART and 689 pregnant women conceiving naturally were recruited during the same period as study subjects. The concentrations of 32 PFAS were measured in early-pregnancy serum of all pregnant women, and four PFAS with the highest co-exposure levels in both groups were included in the subsequent analysis. Multiple linear regression models were performed to evaluate the associations of sociodemographic factors with serum PFAS concentrations in the two groups respectively. Beta coefficients and 95% confidence intervals (CI) were exponentiated to calculate the ratio of the geometric mean (GM) of PFAS concentrations after each unit change in the independent variable. Results Perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), 6∶2 chlorinated polyfluoroethersulfonic acid (6∶2 Cl-PFESA), and perfluorohexanesulfonic acid (PFHxS) were four major PFAS in serum of pregnant women conceiving through ART and conceiving naturally, and the concentrations of PFOA, PFOS, and 6∶2 Cl-PFESA were higher in pregnant women conceiving through ART than in pregnant women conceiving naturally (P <0.05). The results of multiple linear regression analysis showed that age at pregnancy and household income were associated with serum PFAS levels in both groups. The serum concentrations of PFOS were higher in pregnant women aged ≥35 years old who conceiving through ART (GM ratio=1.26, 95%CI: 1.04, 1.54) and conceiving naturally (GM ratio=1.24, 95%CI: 1.08, 1.42) than pregnant women aged <30 years old respectively. Pregnant women conceiving through ART and conceiving naturally whose household annual income >300000 CNY had lower serum concentrations of PFOA [GM ratio (95%CI): 0.82 (0.72, 0.95) and 0.89 (0.81, 0.97), respectively] and PFHxS [GM ratio (95%CI): 0.66 (0.51, 0.86) and 0.77 (0.66, 0.90), respectively] than those women whose household annual income <200000 CNY. Additionally, pregnant women conceiving naturally with a graduate education or above had lower serum 6∶2 Cl-PFESA concentrations than women with an education below college (GM ratio: 0.81), and multiparous pregnant women conceiving naturally had higher serum concentrations of PFOS, 6∶2 Cl-PFESA, and PFHxS than primiparous pregnant women (GM ratio: 1.14, 1.25, and 1.27 respectively). Conclusion Although differences in serum PFAS levels are found between pregnant women conceiving through ART and women conceiving naturally in this study, maternal age and household income are common determinants of PFAS exposure levels in both populations. We find no special sociodemographic factors to affect PFAS concentrations of pregnant women conceiving through ART compared to pregnant women conceiving naturally. Further research is required to explore other potential factors.

Preconceptional exposure levels and determinants of multiple pesticides among women undergoing assisted reproductive technology in Shanghai / 环境与职业医学

Background Pesticide exposure may impact the reproductive health of women undergoing assisted reproductive technology (ART). However, data on pesticide exposure levels in women undergoing ART in China are scarce, and current research on influencing factors is limited. Objective To evaluate the preconceptional pesticide exposure levels and identify potential determinants among women undergoing ART. Methods This study was designed as a cross-sectional survey and recruited 508 women undergoing ART from July 2017 to December 2018 at the fertility clinic of the International Peace Maternity and Child Health Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. Gas chromatography/liquid chromatography-tandem mass spectrometry was used to determine the metabolite concentrations of organophosphate pesticides (OPs), pyrethroid pesticides (PYRs), and neonicotinoid pesticides (NEOs) in urine. The sum of molar concentrations of the three pesticide classes (∑2OPs, ∑2PYRs, and ∑2NEOs) were calculated. A questionnaire was used to collect demographic characteristics, dietary habits, and behavioral information. Multiple linear regression was employed to analyze the associations of demographic characteristics, dietary habits, and behavioral variables with the concentrations of pesticide metabolites in urine among the participants. Results The median creatinine-adjusted concentrations of ∑2OPs, ∑2PYRs, and ∑2NEOs in this study were 419.77, 2.95, and 20.36 nmol·g−1, respectively. The multiple linear regression results showed that the urinary concentration of ∑2OPs was 42.88% higher in the participants with daily vegetable intake than in those who consumed vegetables ≤3 d per week (P<0.05), and the urinary concentration of ∑2PYRs was 37.24% higher in the participants with daily fruit intake than in those who consumed fruits ≤3 d per week (P<0.01). Similarly, the urinary concentrations of ∑2NEOs were 24.51% and 29.30% higher in the participants who consumed fruits daily and 4-6 d per week, respectively, than in those who consumed fruits ≤3 d per week (P<0.05). Besides, we also found that the urinary concentration of ∑2PYRs was negatively correlated with body mass index (BMI) in the participants (P<0.05). Furthermore, the urinary concentration of ∑2NEOs was not only positively correlated with age (P<0.05), but also significantly associated with pet ownership and infertility causes among the participants. Specifically, the participants who continued to own pets after conception had a 30.11% higher urinary concentration of ∑2NEOs than those who never owned pets (P<0.05), and the participants with infertility due to female factors had a 24.10% lower urinary concentration of ∑2NEOs than those who received ART treatment for infertility caused by male factors (P<0.05). Conclusion The women undergoing ART in Shanghai are widely exposed to pesticides. Age, BMI, frequency of vegetable and fruit intake, pet ownership, and infertility causes may be related to the pesticide exposure levels in this population. However, more human data are needed to confirm these findings.

Epidemiological investigation of occupational hand-arm vibration disease caused by handheld workpiece polishing / 中国职业医学

ObjectiveTo explore the influencing factors of occupational hand-arm vibration disease (OHAVD) caused by handheld workpiece polishing. Methods A total of 222 OHAVD patients (case group), 275 hand-transmitted vibration-exposed workers (exposed group) and 243 healthy workers without hand-transmitted vibration exposure (control group) in a sports equipment manufacturing enterprise were selected as the study subjects using the convenience sampling method. Worksite survey of occupational health was conducted on these three groups, and the human vibration measurement equipment was used to measure the vibration exposure level of handheld vibration among the study subjects. The 8-hour energy equivalent frequency-weighted vibrating acceleration ［A(8)］ and cumulative vibration exposure level (CVEL) were calculated. Results The prevalence of coldness, numbness, tingling fingers, and vibration-induced white finger was higher in the exposed group and the case group compared with the control group (all P<0.05). The prevalence of the above-mentioned hand symptoms was higher in the case group compared with the exposed group (all P<0.05). The A(8) and CVEL levels of the study subjects in the case group were higher than those in the exposed group (all P<0.05). Binary logistic analysis result showed that age and CVEL were both influencing factors of OHAVD (all P<0.05). According to the restricted cubic spline models, CVEL of the study subjects in the exposed group had a positive nonlinear dose-response relationship with the risk of OHAVD (overall trend P<0.01, nonlinear P<0.01), indicating an increasing risk of OHAVD with increasing CVEL. Conclusion Hand-transmitted vibration exposure is a risk factor for OHAVD. Early intervention should be carried out for hand-transmitted vibration-exposed individuals to reduce vibration-exposed levels and control vibration exposure time.

A modal study of the effect of adjusting density exposure steps on image quality and radiation dose in digital mammography / 中华放射学杂志

Objective:To investigate the effect of adjusting density exposure steps on image quality and radiation dose in digital mammography.Methods:Using the automatic exposure control (AEC) mode of the digital mammography machine, five different gland thicknesses of 4.3, 5.3, 6.3, 7.3, and 8.3 cm were simulated by attaching 0, 1, 2, 3, and 4 PMMA plexiglass plates under the RMI-156 modal body, and the density exposure steps were adjusted to -3, -2, -1, 0, 1, 2, 3, and 4 for each thickness. The target/filter combination, tube voltage, tube current, incident body surface dose (ESD), incident surface air kerma (ESAK), half-value layer (HVL) and the average glandular dose displayed by the device (displayed AGD) were recorded at each step and thickness, and the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), figure of merit (FOM) and the calculated average glandular dose (calculated AGD) were calculated. Then, the display effects of simulated fibers, simulated calcifications and simulated masses within the modal body were scored subjectively, and the changes in image quality and radiation dose at different steps were analyzed, and the relationships between ESD and ESAK, displayed AGD and calculated AGD, and displayed AGD/ESD and calculated AGD/ESAK were analyzed. A linear fit was used for the steps with SNR, CNR, and FOM, and an exponential function curve fit was used for the steps with mAs, ESAK, and calculated AGD. The differences between ESD and ESAK, displayed AGD and calculated AGD, and displayed AGD/ESD and calculated AGD/ESAK were analyzed by paired-samples t test. Results:The CNR and SNR of mammographic images rose and fell by about 8% with each increase or decrease of one step. The scores of image simulated fibers, simulated calcifications, and simulated masses showed an overall upward trend with increasing steps, but there were still cases where the scores decreased with increasing grades. FOM varied from 97% to 104% at each grade with little variability. ESD, ESAK, displayed AGD, and calculated AGD, which could measure radiation dose, showed an exponential trend of increasing function with increasing steps, with a variation of about 63% to 165%. There were statistically significant differences ( t=-9.61, P=0.001) between ESD (15.14±10.08) and ESAK (16.66±11.07). However, there were no statistically significant differences ( t=1.20, P=0.240) between displayed AGD and calculated AGD, which were 3.66±2.18 and 3.61±1.99, respectively. Conclusions:The adjustment of density exposure steps can make the image quality change linearly and the radiation dose change exponentially with increasing speed, and the mode and magnitude of the adjustment are appropriately stable with high application value.

Associations between urinary paraben levels and obesity of 10-year-old children / 环境与职业医学

Background Parabens, a widely used class of preservatives, are suspected to be potential obesogens as emerging endocrine disrupting chemicals with reproductive and developmental toxicity. Objective To analyze five urinary parabens (PBs) and estimate the associations of exposure to PBs with adiposity measures in 10-year-old school-age children. Methods A total of 471 school-age children aged 10 years from the Sheyang Mini Birth Cohort were enrolled in this study. A questionnaire survey was conducted to collect socio-demographic information, physical activity, and dietary intake. Weight, height, and waist circumference of children were measured, and age- and sex-adjusted body mass index (BMI-Z score) was calculated. Spot urine samples were collected during the follow-up visits. Urinary concentrations of five PBs including methyl-paraben (MeP), ethyl-paraben (EtP), propyl-paraben (PrP), butyl-paraben (BuP), and benzyl-paraben (BzP) were detected by gas chromatography-tandem mass spectrometry (GC-MS/MS). Generalized linear models (GLMs) and Bayesian kernel machine regression (BKMR) models were applied to estimate associations of individual/overall urinary PBs concentrations with BMI Z-score and waist circumference. Results The positive rates of selected five urinary PBs were in the range from 78.98% to 98.94%. The urinary PBs concentrations (geometric mean) were in the range of 0.31-5.43 μg·L−1. The children's BMI Z-score and waist circumference (mean ± standard deviation) were (0.56±1.40) and (67.62±10.07) cm respectively. The GLMs results showed that the urinary BzP concentration was negatively associated with waist circumference (b=−0.08, 95%CI: −0.14, −0.02; P=0.01). In sex-stratified analysis, the urinary concentration of BzP was negatively associated with BMI-Z score (b=−0.59, 95%CI: −0.88, −0.30; P<0.001) and waist circumference (b=−0.80, 95%CI: −1.23, −0.37; P<0.001) in boys, but not in girls. The BKMR results also found significant negative correlations of urinary BzP concentrations with BMI-Z score and waist circumference, which were consistent with the GLM results. Conclusion The selected 10-year-old children are extensively exposed to PBs in the study area. Furthermore, childhood PBs exposure may have potential impacts on childhood adiposity measures with sex-specific effects.

Research progress on content and detection methods of microplastics/nanoplastics in biological samples / 环境与职业医学

Plastic products are widely used in various fields, and the discarded plastics in the environment can be degraded into microplastics (MPs) or even nanoplastics (NPs), which significantly increases the risk of organism exposure. MPs/NPs have been found in aquatic organisms, birds of prey, and even humans. The detection of plastic particles in biological samples is more complicated than that in environmental samples. Biological samples are mainly composed of various organic substances such as proteins and lipids, which makes the pretreatment process particularly critical. Effective detection and accurate quantification of MPs/NPs are crucial to health risk assessment. In this paper, the exposure levels and composition of MPs/NPs in different tissues and organs of the human body, aquatic organisms, and birds of prey were reviewed. The digestion of biological samples (acids, bases, enzymes, and hydrogen peroxide digestion protocols) and MPs/NPs identification methods (spectroscopy and chromatography) were compared and their advantages and disadvantages were assessed, providing a methodological basis for plastic exposure risk assessment and pollution control.

Peripheral circulation and peripheral nerve injury in workers exposed to vibration at two different frequencies / 环境与职业医学

Background Hand-arm vibration disease is harmful to human body, but there are no effective diagnosis and treatment so far, and current occupational exposure limits underestimate the health damage caused by high-frequency vibration exposure. Objective To evaluate and compare the damage to workers' peripheral circulation and peripheral nerve caused by different frequencies of vibration operation. Methods Drilling workers (n=187) from a mining company in Shandong Province and golf club head grinding workers (n=228) from a sports equipment factory in Guangdong Province were selected as study subjects. Hand symptoms were investigated. SV106 vibration meter was used to measure the target operation-associated vibration frequency spectrum. The 8 h energy-equivalent frequency weighted acceleration, cumulative vibration exposure level (CVEL), and the working age related to causing white finger in 10% of an exposed group were calculated. Result The study subjects were all male. More grinding workers reported hand symptoms than the drilling workers, e.g. peripheral circulation injury (52.6% vs 19.3%), peripheral nerve injury (71.5% vs 23.0%), hand stiffness (64.0% vs 7.0%), and deformed fingers (69.7% vs 4.3%) (all P<0.001). The main vibration frequencies of grinding operation (500-800 Hz) were much higher than those of drilling operation (125~160 Hz). CVEL and working age of vibration exposure showed a linear rising relationship with the cumulative prevalence rate of peripheral circulation and peripheral never injury, the fitting lines all showed good fitting effects (R2=0.812-0.988), and the slope of the fitting line of the grinding workers was larger than that of the drilling workers. The working age of vibration exposure associated with 10% cumulative prevalence of white finger was shorter in the grinding workers than in the drilling workers (6.81 years vs 10.27 years). According to the ISO prediction formula, the working age of vibration exposure was associated with 10% white finger prevalence shorter in the drilling workers than in the grinding workers (3.12 years vs 8.23 years). Conclusion Both the vibration exposure level and the prevalence of hand symptoms are high in two groups of workers with different vibration frequencies, and vibration exposure at a higher frequency tends to have severer damage to workers' hands.

The exposure levels of phthalic acid esters in population: a review / 预防医学

@#Phthalic acid esters (PAEs) are commonly used plasticizers and solvents. Human body is exposed and absorbed mainly through diet, skin and air inhalation. The biological samples such as urine, blood, saliva, semen and breast milk generally contain PAEs and their metabolites, but the concentrations of PAEs metabolites vary in different samples. In the general population, the levels of PAEs are higher in children than in adults, and higher in women than in men; the levels of PAEs are higher in the occupational population than in the general population. In this paper, the research of PAEs related human biomonitoring in the general population and occupational population at home and abroad is reviewed, so as to provide the basis for reducing the exposure of PAEs and related health risk.

Pollution， human exposure and harmful effects of neonicotinoid pesticides / 上海预防医学

Neonicotinoid is a kind of neuroactive pesticide， and it has become the most widely used pesticide in the world. In recent years， neonicotinoid has been detected in the environment and food， suggesting that human can be exposed to this kind of pesticide through drinking water， ingestion and respiration， which poses potential health hazards to human. However， there is no comprehensive report on the pollution level of neonicotinoid pesticides in the environment and food and the impact on human health. In this paper， the pollution status， population exposure level and potential health risks of neonicotinoid pesticides in water， air and food were reviewed. We found that neonicotinoid residues are widespread in fruits and vegetables， of which imidacloprid has the highest detection rate. Except for a few samples with excessive neonicotinoid detection， the detection level in most samples did not exceed national food safety standards. A variety of neonicotinoid pesticides have been detected in the air， surface water， tap water and drinking water. External exposure studies in the population have shown that ingestion is the main route of exposure to neonicotinoid， and the external exposure level is much lower than its chronic reference dose. The internal exposure study mainly detected the concentration of neonicotinoid pesticides and their metabolites in urine. A variety of neonicotinoid pesticides and their metabolites are detected in urine， and the concentration range is ng/ml level. Internal exposure studies found that the detection rate of thiamethoxam and dinotefuran in urine is higher， and the detection rate of neonicotinoid in Asian countries is higher than that in European and American countries. Occupational exposure studies found that neonicotinoid exposure levels increased after pesticide spraying， and the exposure levels in rural areas where pesticides were commonly used were higher than those in neighboring urban areas. Animal experiments have found that neonicotinoid pesticides have reproductive toxicity， genetic toxicity， neurotoxicity， immunotoxicity， liver toxicity and nephrotoxicity to non-target organisms. Cell experiments suggest that neonicotinoid is an endocrine disruptor. The symptoms of acute exposure in humans are related to the exposure dose， route and physical condition of the exposed person， which ranges from mild symptoms （nausea， vomiting， headache and diarrhea） to death. Population epidemiological studies have shown that chronic exposure to neonicotinoid pesticides is associated with adverse health effects in humans such as neonatal tetralogy of Fallot， anencephaly， and adverse mental symptoms.

Occupational Health Risk Assessment of Benzene, Toluene, and Xylene in Shanghai / 生物医学与环境科学（英文）

Objective@#This study was designed to conduct a retrospective and systematic occupational health risk assessment (OHRA) of enterprises that used benzene, toluene, and xylene (BTX) in Shanghai, China.@*Methods@#All data for the study were obtained from 1,705 occupational health examination and evaluation reports from 2013 to 2017, and a semiquantitative model following Chinese OHRA guidelines (GBZ/T 298-2017) was applied for the assessment.@*Results@#The selected enterprises using BTX were mainly involved in manufacturing of products. Using the exposure level method, health risk levels associated with exposure to BTX were classified as medium, negligible, or low. However, the risk levels associated with benzene and toluene were significantly different according to job types, with gluers and inkers exhibiting greater health risks. For the same job type, the health risk levels assessed using the comprehensive index method were higher than those using the exposure level method.@*Conclusion@#Our OHRA reveals that workers who are exposed to BTX still face excessive health risk. Additionally, the risk level varied depending on job categories and exposure to specific chemicals. Therefore, additional control measures recommended by OHRA guidelines are essential to reduce worker exposure levels.

Association between Respirable Dust Exposure and Respiratory Health among Cement Workers

@#Introduction: Cement industry contributes to the major constituent of airborne dust in the atmosphere. This study aims to determine the level of respirable cement dust exposure associated with workers’ respiratory health. A cross-sectional study was carried out among 84 administration workers as the comparative group and 84 manufacturing workers as the exposed group. Method: A set of validated questionnaires was used to obtain some pertained background information as well as respiratory symptoms among the respondents. Personal Air Sampling Pump was used for assessing personal exposure towards cement dust in 8 hours. For lung function performance, a Spirometry test was carried out and Fractional Exhaled Nitric Oxide (FENO) test was conducted to assess airway inflammation. Results: The median for personal exposure level to respirable dust of manufacturing workers was 2.68 (5.90) mg/ m3 with range 0.351 to 10.60 mg/m3. The lung function abnormality among the manufacturing workers was FVC% (PR=3.82, 95% CI=1.52-9.58) and FEV1% (PR=5.16, 95% CI=1.65-16.10). Cough was reported to occur the most likely among the manufacturing workers (PR=2.40, 95% CI=1.12-5.15). After adjusting the smoking status, the prevalence of phlegm and cough were 35.7% and 29.8% respectively. 16.7% of manufacturing workers recorded a high level of FENO. The increasing exposure to respirable dust significantly reduces the FVC% of manufacturing workers (r=-0.36, p=0.05). Conclusion: The personal exposure to respirable cement dust increases the risk of lung impairment by highly developing respiratory health symptoms, reducing lung function level and increasing the higher level of airway inflammation among highly exposed workers.

Evaluation on occupational exposure to whole body vibration in workers of a hydroelectric power station / 中国职业医学

OBJECTIVE: To examine the level of occupational exposure to whole body vibration( WBV) in a hydroelectric power station,and evaluate its effects on workers' health. METHODS: A hydroelectric power station in Hangzhou City was chosen as study subject by using judgment sampling method. The level of WBV exposure to workers and high vibration level areas were measured,and the vibration frequency was analyzed. The comfort and allowing duration of occupational exposure in WBV exposed workers was evaluated. RESULTS: The median root-mean-square of accelerometer acceleration of WBV exposure in generator floor,turbines-floor,middle-floor,hydraulic floor of the hydroelectric power station were 0. 894,0. 995,1. 095 and 0. 904 m/s~2,respectively. The central frequency of WBV in this station was 1. 25 Hz. Among the 105 monitoring spots,8. 6% of WBV exposed workers of the spots did not perceive or feel uncomfortable,but 91. 4%of them felt uncomfortable or very uncomfortable. Only 12. 4% of the WBV exposed workers tolerated more than 8 hours of WBV occupational exposure. CONCLUSION: There is an occupational hazard of WBV in this hydroelectric power station.The low frequency vibration with central frequency below 1. 25 Hz is the key control point of the WBV of this hydroelectric power station.