In the present study,the levels of alkylphenols(APs)and alkylphenol ethoxylates(APEs)in indoor dust of three different microenvironments were measured and daily intake via dust ingestion estimated.Alkylphenols and alk...In the present study,the levels of alkylphenols(APs)and alkylphenol ethoxylates(APEs)in indoor dust of three different microenvironments were measured and daily intake via dust ingestion estimated.Alkylphenols and alkylphenol ethoxylates were extracted with the aid of sonication and analyzed by gas chromatography mass spectrometry after heptafluorobutyric anhydride derivatization.The concentration values of these pollutants ranged from 1918e10935 ng g1;343e12438 ng g1 and 1122 e15324 ng g1 in dust samples from homes,computer laboratories and offices,respectively.In all the microenvironment studied,di-NPE and mono-NPE were the most abundant isomers suggesting widespread use of NPE-based consumer products in the studied microenvironments.The daily exposure dose(DED)was estimated using min,mean and max concentrations of APs and APEs detected in respected microenvironments.The worst case scenario for the exposure of APEs was highest for toddlers at 146 ng kg1 bw day1 followed by teenagers at 11.3 ng kg1 bw day1 and adults at daily exposure of 8.53 ng kg1 bw day1.Though the daily exposure doses are low,there is a cause for concern as these surfactants are not regulated in many developing countries and their use may be increasing.展开更多
This study evaluates the characteristic levels,sources and risk of human exposure to polycyclic aromatic hydrocarbons(PAHs)in indoor dusts from electronic repair workshops in southern Nigeria.The dust samples were col...This study evaluates the characteristic levels,sources and risk of human exposure to polycyclic aromatic hydrocarbons(PAHs)in indoor dusts from electronic repair workshops in southern Nigeria.The dust samples were collected by gentle sweeping with a brush and dustpan,and subsequently dried and extracted with hexane/dichloromethane by ultrasonication.The extracts were purified on a silica gel/alumina column,and then analysed for their PAH content by means of gas chromatography-mass spectrometry.The concentrations of PAHs in the electronic repair workshop dusts ranged between 205 and 2963 mg kg1.The compositional patterns indicate the dominance of 5-and 3-ring PAH homologues.The estimated benzo[a]pyrene carcinogenic(BaPTEQ)and mutagenic(BaPMEQ)potency concentrations ranged from 67 to 401 mg kg^-1 and 56.5e277 mg kg^-1 respectively.The non-cancer risk(hazard index,HI)arising from human contact with PAHs in the electronic repair workshop dusts were less than one for all human subject age groups indicating that there is no considerable non-cancer risk.The cancer risk values for the ingestion and dermal contact routes were greater than the acceptable risk of 10^-6,which suggests that there is a considerable cancer risk associated with unconscious ingestion and dermal contact with dust particles from these electronic repair workshops.The isomeric ratios for the PAHs in the dust samples and principal component analysis suggest that combustion of biomass and vehicular emissions were responsible for the presence of PAHs in the electronic repair workshop dusts.展开更多
文摘In the present study,the levels of alkylphenols(APs)and alkylphenol ethoxylates(APEs)in indoor dust of three different microenvironments were measured and daily intake via dust ingestion estimated.Alkylphenols and alkylphenol ethoxylates were extracted with the aid of sonication and analyzed by gas chromatography mass spectrometry after heptafluorobutyric anhydride derivatization.The concentration values of these pollutants ranged from 1918e10935 ng g1;343e12438 ng g1 and 1122 e15324 ng g1 in dust samples from homes,computer laboratories and offices,respectively.In all the microenvironment studied,di-NPE and mono-NPE were the most abundant isomers suggesting widespread use of NPE-based consumer products in the studied microenvironments.The daily exposure dose(DED)was estimated using min,mean and max concentrations of APs and APEs detected in respected microenvironments.The worst case scenario for the exposure of APEs was highest for toddlers at 146 ng kg1 bw day1 followed by teenagers at 11.3 ng kg1 bw day1 and adults at daily exposure of 8.53 ng kg1 bw day1.Though the daily exposure doses are low,there is a cause for concern as these surfactants are not regulated in many developing countries and their use may be increasing.
基金BSM acknowledges the support from the University of KwaZulu-Natal and National Research Foundation of South Africa(NRF).
文摘This study evaluates the characteristic levels,sources and risk of human exposure to polycyclic aromatic hydrocarbons(PAHs)in indoor dusts from electronic repair workshops in southern Nigeria.The dust samples were collected by gentle sweeping with a brush and dustpan,and subsequently dried and extracted with hexane/dichloromethane by ultrasonication.The extracts were purified on a silica gel/alumina column,and then analysed for their PAH content by means of gas chromatography-mass spectrometry.The concentrations of PAHs in the electronic repair workshop dusts ranged between 205 and 2963 mg kg1.The compositional patterns indicate the dominance of 5-and 3-ring PAH homologues.The estimated benzo[a]pyrene carcinogenic(BaPTEQ)and mutagenic(BaPMEQ)potency concentrations ranged from 67 to 401 mg kg^-1 and 56.5e277 mg kg^-1 respectively.The non-cancer risk(hazard index,HI)arising from human contact with PAHs in the electronic repair workshop dusts were less than one for all human subject age groups indicating that there is no considerable non-cancer risk.The cancer risk values for the ingestion and dermal contact routes were greater than the acceptable risk of 10^-6,which suggests that there is a considerable cancer risk associated with unconscious ingestion and dermal contact with dust particles from these electronic repair workshops.The isomeric ratios for the PAHs in the dust samples and principal component analysis suggest that combustion of biomass and vehicular emissions were responsible for the presence of PAHs in the electronic repair workshop dusts.
