Indoor air pollutants impact human health,comfort and productivity.The method of photocatalysis has been applied mainly in flow reactors and little information is available on indoor air pollutant removal in airtight reactors.In the paper,experiments were carried out to remove formaldehyde(HCHO),ammonia(NH_3) and volatile organic compounds(VOCs)in the airtight and ventilated chambers.Results demonstrated that 90.4%of HCHO,92.3%of NH_3 and 57.9%of VOCs were removed in the amine adsorption process,while 67.5% (hereinbefore,these are the mass fraction)of HCHO,60.0%of NH_3,and 61.2%of VOCs were removed in the photocatalytic process.However,ozone-assisted photocatalytic process showed great potential to degrade indoor air pollutants in the ventilated chamber.Factors and mechanisms of the photocatalytic degradation of HCHO, NH_3 and VOCs were also discussed.
To assess the neurotoxic effects and redoxresponses of Aroclor 1254 (A1254) on perinatallyexposed rat offspring, A1254 was administered bygavage from gestational day (GD) 6 to postnatal day(PND) 21. Neurobehavioral development,antioxidant enzyme activities, lipid peroxidation(LPO), nitric oxide (NO), and NO synthase (NOS)levels were analyzed in the offspring.Neurobehavioral development analysis revealeddelayed appearance of the righting reflex, negativegeotaxis, and cliff drop test responses in A1254exposed group. Developmental A1254 exposurealso caused oxidative stress in the brain of PND 22offspring via reductions in the activity of SOD andGSH-Px, and by promoting a rise in the levels of NOand NOS.
Mercury( Hg) concentrations were determined in human hair,blood and urine samples from Tieling coal mine area,to assess the potential health risks associated with Hg due to coal mining activities. The total Hg levels in hair( average 0. 87 μg / g) and blood( average 3. 74 μg /L) of coal miners were quite low at around the same levels as the general population, but the urine Hg levels( average 12. 13 μg /L) were much higher than those from administrators and control group. This study indicated that workers mainly exposed to inorganic Hg through long-time inhalation contaminated air and dust; however other population mainly exposed to methylmercury( Me Hg).
Fetuses and neonates are known to be high-risk groups for Methylmercury(MeHg)exposure.MeHg can be transferred to the fetus through the placenta and to newborn offspring through breast milk.The aim of the present study was to investigate the neurotoxic effects of low doses of MeHg(1 and 5 μg/m L in drinking water) administration,from gestational day 1 to postnatal day(PND) 21,on the neurobehavioral development of rats.The results showed that the no-observed-effect level of MeHg is somewhere in the range of 1-4 μg/mL.Neurobehavioral development analysis revealed a delayed appearance of cliff drop and negative geotaxis reflexes in the 5 μg/mL MeHg exposure group.Developmental exposure to MeHg affected locomotor activity functions for the females,but not for the males,implying that the female pups were more vulnerable than the male pups.All pups exposed to 5 μg/mL of MeHg showed a significant deficit in motor coordination in the rotarod test compared with controls,and the highest accumulated concentrations of Hg were found in the cerebellum,followed by the hippocampus and cerebral cortex,indicating that the cerebellum is a possible target for MeHg toxicity.We demonstrated adverse effects of developmental exposure to MeHg associated with tissue concentrations very close to the current human body burden of this persistent and bioaccumulative compound.
Organoarsenics are widely used as growth promoters in poultry industry,resulting in arsenic(As)accumulation in poultry litter.A greenhouse pot study was implemented to investigate the fate of arsenic originated from poultry litter and their effects on the growth of Brassica napus(oilseed rape),and assess their potential health risks.Five poultry litter application rates(0,5%,10%,20%and 40%)were used,dividing into two groups:one for soil incubation(SI)and the other for plant cultivation(PC).Experimental results indicated that the total arsenic for composted poultry litter was(10.94±0.23)mg/kg,As(V)and As(III)decreased while methylated arsenic increased after 21 d in SI and PC treatments.Seed germination rates were negatively correlated with monomethylarsenic acid(MMA,R2=0.63,p<0.05).The length and biomass of roots and shoots were significantly inhibited by poultry litter,but plant length of 5%treatments was slightly stimulated.Within an average weekly intake of 0.5 kg Brassica napuss,the risk quotient(RQ)values induced from roots nearly all surpassed the acceptable limit(1),were two orders magnitude higher than shoots.According to the potential risk to order,child exhibited the highest risk,adolescent ranked secondly,and adult exhibited the lowest risk.Hence,people should better avoid intake Brassica napus roots to reduce arsenic potential risk.