OBJECTIVETo study long-term effect on renal function exposed to environmental cadmium.

METHODSStratified random sampling and cluster sampling method of epidemiological investigations were carried out in northern Guangdong province between April, 2011 and August, 2012. A total of 167 residents who lived in high cadmium exposure area for more than 15 years, aged above 40 were selected in exposed group. Moreover, A total of 145 residents who had similar living and economic conditions and lived in local for more than 15 years, aged above 40 were selected in control group. We used health questionnaires and medical examinations in order to acquire their health status. Home-harvested rice and vegetables were collected using quartering method for detection of cadmium level. Urine specimens of residents were collected for detection of cadmium level and creatinine as well as renal dysfunction biomarkers, namely, N-acetyl-beta-D-glucosamidase (NAG), β2-microglobulin (β2-MG), and retinol binding protein(RBP), respectively. The analysis of spearman rank correlation and multiple regression were used to investigate the relationships between age, urinary cadmium levels and renal injury biomarkers.

RESULTSThe cadmium levels in rice and vegetables of exposed group were 0.75 and 0.10 mg/kg, both were significantly higher than 0.07 and 0.01 mg/kg in the control group (Z values were -6.32 and -7.84, all P values < 0.001). The urinary cadmium level of exposed group was 8.29 µg/g · cr, which was higher than that of the control group 2.03 µg/g · cr with significant difference (Z value was -11.39, P < 0.001). After stratified the total population by age, the urinary cadmium level in 40-49 years, 50-59 years and ≥ 60 years subgroups were 7.22, 8.71, and 13.10 µg/g · cr, which both were significantly higher than 1.80, 2.04, and 2.05 µg/g · cr in the control group (Z values were -5.22, -7.41, and -7.14, all P values < 0.001). After stratified the total population by gender, the urinary cadmium level of male and female were 5.12 and 12.36 µg/g · cr, which both were significantly higher than 1.79 and 2.16 µg/g · cr in the control group (Z values were -7.68 and -9.03, all P values < 0.001). Comparing the differences of renal dysfunction biomarkers (NAG, β2-MG, RBP) between two groups. The level of urinary β2-MG and RBP of exposed group were 0.21 and 0.04 µg/g · cr, which were higher than 0.05 and 0.00 µg/g · cr of the control group with significant difference (Z value was -7.08 and -9.65, all P values < 0.001). Pearson correlation analysis showed that NAG, β2-MG and RBP were positively correlated with urinary cadmium and age, the correlation coefficients were 0.57, 0.49, 0.21 and 0.22, 0.26, 0.23 respectively (all P values < 0.001). After adjusting the effect of age, it was appeared that urinary cadmium levels contributed most to the alteration of NAG, β2-MG and RBP, the standardized regression coefficients were 0.57, 0.49 and 0.20 (all P values < 0.001), and suggested that the cadmium body burden was one of the most important factors for renal dysfunction.

CONCLUSIONResidents, who had cadmium contaminated rice and vegetables for a long time, would take the risk of increasing body burden of cadmium and urinary early biomarkers of renal tubular injury that referred to occurrence of renal dysfunction.

Adult ; Aged ; Cadmium ; Creatinine ; Environmental Exposure ; Epidemiologic Studies ; Female ; Food Contamination ; Humans ; Kidney Diseases ; Male ; Middle Aged ; Multivariate Analysis ; Oryza ; Risk ; Time ; Vegetables

OBJECTIVETo explore the association between occupational stress and other socio-psychological factors and work-related unintentional injury in off-shore oil production.

METHODSA cross-sectional survey was conducted among 561 Chinese off-shore oil workers. They were inquired with a self-administered questionnaire involving in socio-demographic characteristics, occupational stress, type A behavior personnel, social support and coping style, and work-related unintentional injury in the past year.

RESULTSSeventy-six (13.5%) workers experienced work-related unintentional injury for once time or more in the past year. A total 141 number of person-times were counted including 18 person-times being serious injury, 26 person-times moderate, and 97 person-times light. After adjustment for age, educational level, marital status, duration of off-shore work and job title, logistic regression indicated that perceived stress from "management problem and relationship with others" were significantly associated with work-related unintentional injuries in the past year (OR = 1.33, 95% CI: 1.05-1.68; P < 0.05). Workers lack of emotional support from friends seemed to less reporting on work-related unintentional injuries (OR = 0.37, 95% CI: 0.22-0.63).

CONCLUSIONThe results implied emphasizing on that the training and guidance as well as better cooperation among the workers might reduce work-related unintentional injuries in off-shore oil industry.

Accidents, Occupational ; prevention & control ; statistics & numerical data ; Adult ; Fuel Oils ; Humans ; Male ; Middle Aged ; Occupational Diseases ; complications ; Stress, Psychological ; complications ; Wounds and Injuries ; etiology ; prevention & control