Fluoride and arsenic exposure affects spatial memory and activates the ERK/CREB signaling pathway in offspring rats.

Fluoride and arsenic are inorganic contaminants that occur in the natural environment. Chronic fluoride and/or arsenic exposure can induce developmental neurotoxicity and negatively influence intelligence in children, although the underlying molecular mechanisms are poorly understood. This study explored the effects of fluoride and arsenic exposure in drinking water on spatial learning, memory and key protein expression in the ERK/CREB signaling pathway in hippocampal and cerebral cortex tissue in rat offspring. Pregnant rats were divided into four groups. Control rats drank tap water, while rats in the three exposure groups drank water with sodium fluoride (100mg/L), sodium arsenite (75mg/L), and a sodium fluoride (100mg/L) and sodium arsenite (75mg/L) combination during gestation and lactation. After weaning, rat pups drank the same solution as their mothers. Spatial learning and memory ability of pups at postnatal day 21 (PND21) and postnatal day 42 (PND42) were measured using a Morris water maze. ERK, phospho-ERK (p-ERK), CREB and phospho-CREB (p-CREB) protein expression in the hippocampus and cerebral cortex was detected using Western blot. Compared with the control pups, escape latencies increased in PND42 pups exposed to arsenic and co-exposed to fluoride and arsenic, and the short-term and long-term spatial memory ability declined in pups exposed to fluoride and arsenic, both alone and in combination. Compared with controls, ERK and p-ERK levels decreased in the hippocampus and cerebral cortex in pups exposed to combined fluoride and arsenic. CREB protein expression in the cerebral cortex decreased in pups exposed to fluoride, arsenic, and the fluoride and arsenic combination. p-CREB protein expression in both the hippocampus and cerebral cortex was decreased in pups exposed to fluoride and arsenic in combination compared to the control group. There were negative correlation between the proteins expression and escape latency periods in pups. These data indicate that exposure to fluoride and arsenic in early life stage changes ERK, p-ERK, CREB and p-CREB protein expression in the hippocampus and cerebral cortex of rat offspring at PND21 and PND 42, which may contribute to impaired neurodevelopment following exposure.

Analysis of Hemogram of Radiation Workers in Tangshan, China.

OBJECTIVES: This study aimed to investigate changes in peripheral blood cells of radiation workers and explore the impact of long-term ionizing radiation (IR) on human peripheral hemogram. METHODS: With a cohort method, we selected 1,392 radiation workers (case group) and 1,430 non-health-ray-exposure history persons (control group) to detect and analyze their peripheral hemogram. FAITH3000 automatic biochemical analyzer was used for blood testing. Examination of peripheral hemogram includes the examination of white blood cells (WBCs), platelet (PLTs), red blood cells (RBCs), hemoglobin (Hb), lymphocytes (LYMs), and mononuclear cells (MOs). The data analysis was conducted with software SPSS19.0. RESULTS: All the peripheral hemogram indicators (WBCs, RBCs, Hb, PLTs, LYMs, and MOs) in the case group, in accordance with the order of radiology diagnostic medical group, industrial inspection group, petroleum logging group, and radiotherapy medical group, showed a significant decreasing trend and were lower than those in the control group (all P < 0.05). Besides, with the increase of radiation seniority and accumulative radiation dose, all the peripheral hemogram indicators (WBCs, RBCs, Hb, PLTs, LYMs, and MOs) in the case group dramatically decreased and were lower than those in the control group (all P < 0.05). Seniority was in negative association with the expressions of WBCs, PLTs, RBCs, Hb, LYMs, and MOs and radiation dose with Hb, LYMs, and MOs (all P < 0.05). CONCLUSION: Long-term IR has some effects on the health of radiation workers, thus protective measures should be further strengthened.

Relationship of cumulative dust exposure dose and cumulative abnormal rate of pulmonary function in coal mixture workers.

To investigate the dose-response relationship between cumulative dust exposure (CDE) and cumulative abnormal rate of pulmonary function in coal mixture workers. Three hundred and twenty eight coal mixture workers (exposed group) and 169 nondust-exposed workers (control group) were recruited. Basic information data were collected and pulmonary function tests were performed. Pulmonary function was compared between the two groups after comparing smoking behaviors. Pulmonary function indices [forced vital capacity in 1 second after full inspiration (FVC)%, forced expiratory volume (FEV)1%, and FEV1/FVC%] were compared among groups stratified by service length (exposure duration). The relationship between CDE dose and cumulative abnormal rate of pulmonary function in coal mixture workers was analyzed. Abnormal rate of pulmonary function in the exposed group (35.1%) was significantly higher than the control group (10.1%; p < 0.001); FVC%, FEV1%, and FEV1/FVC% in the exposed group decreased significantly compared with the control group (all p < 0.05). Differences in FVC%, FEV1%, and FEV1/FVC% among coal mixture workers stratified by exposure duration in the exposed group were statistically significant (all p < 0.05). The discernible increase in the cumulative abnormal rate was observed, from ≥ 1000 mg/m(3)·years group to ≥ 1700 mg/m(3)·years group. Correlation analysis revealed a positive correlation between the CDE dose and the cumulative abnormal rate of pulmonary function. Higher abnormal pulmonary function rate was found among coal mixture workers, characterized by decreased pulmonary function indices. Our results suggested a positive relationship between CDE dose and cumulative abnormal pulmonary function rate, and a rapid increase in cumulative abnormal rate within a certain range of CDE dose. A lower limit value of 1000 mg/m(3)·years has reference significance.