Humans and animals can be exposed to Dioxins and Furans through ingestion of fatty food, skin contact, and breathing contaminated air. Resulting health problems include skin disease, immune problems, and cancers. Mana...Humans and animals can be exposed to Dioxins and Furans through ingestion of fatty food, skin contact, and breathing contaminated air. Resulting health problems include skin disease, immune problems, and cancers. Managing the release of these chemicals is therefore important. The Stockholm Convention on Persistent Organic Pollutants requires parties to adopt measures that reduce sources of these chemicals. Sierra Leone developed its National Implementation Plan (NIP) in 2008, in compliance with this requirement. However, no known further steps have been taken, particularly at community level. In 2013, the UNDP’s GEF/SGP funded a pilot project to manage the release of Dioxins and Furans from two dumpsites in Freetown, Sierra Leone. This work was sponsored with funds from that project. The work sought to delineate the exposure of communities within and around the Bormeh-Kingtom dumpsite (Kingtom, Kolleh town, Ascension town, Crab town, and Congo town) to the chemicals. The study considered sources of exposure, relative quantities generated per year, and the routes of exposure. This exposure study is a first step in managing the release from those sources. Enumerators deployed at the dumpsite every day, 7:00 AM to 6:00 PM, for three months, quantifying and recording source materials. The amount of source materials dumped per day informed calculation of Dioxin/Furan releases in grams toxicity equivalence per year. The results revealed a release of 128.914 g TEQ/year in air and residue. This implies that the communities are at high risk of inhalation and dermal exposure. Livestock, mainly pigs, are also exposed as they feed on the waste deposited in the dumpsite. Humans in turn feed on the livestock, a recipe for biomagnification. The project team has been working on developing Best Management Practices to suppress the release of the chemicals.展开更多
Concentrations of selected heavy metals, nutrient elements and PAHs in farms and produce (cassava tubers and oil bean seeds) from 4-year-old crude oil impacted areas (Ekore and Uduvwoku) and a non-oil-impacted area (O...Concentrations of selected heavy metals, nutrient elements and PAHs in farms and produce (cassava tubers and oil bean seeds) from 4-year-old crude oil impacted areas (Ekore and Uduvwoku) and a non-oil-impacted area (Okpe), all in Ughelli South Local Government Area, Delta State, Nigeria, were investigated to ascertain degree of risk posed. A random sampling design was chosen with three replications. Results obtained revealed significantly (P < 0.05) elevated (mg·kg<sup>-1</sup>) Cd (0.240, 0.140) and Cr (1.327, 3.122) in cassava samples for Ekore and Uduvwoku respectively in comparison to non-detectable amount for those of non-impacted source and exceeded set WHO limits of 0.1 and 0.05 mg·kg<sup>-1</sup> respectively. Although PAHs were low, oil spill increased available levels by factor of 2.5 and 5 for Ekore and Uduvwoku respectively. Again, Cd and Cr exceeded WHO limit for study impacted soils. Available N, P and K decreased (%) by 56.1, 28.5 and 2.4 for Ekore and 82.9, 39.9 and 45.5 for Uduvwoku Cassava samples. Nutrient profiling in oil bean revealed % reduction in avaliable N, P and K by 33.7, 47.7 and 57.9 and 28.9, 76.3 and 39.8 for Ekore and Uduvwoku samples respectively. For oil bean, Cd and Cr did not differ markedly between polluted samples but exceeded WHO limits. Other studied contaminants fell within limits. In soils, available N, P and K decreased (%) by 39.6, 79.1 and 27.4 for Ekore and 53, 88.1 and 45.5 for Uduvwoku samples. Low pH of 5.3 and 5.7 in Ekore and Uduvwoku respectively may increase the leachability of Cr into groundwater. Biopersistent Cd and Cr were found to biomagnify up the food chain and may impair major processes. Although PAHs were relatively low, their % composition was more of High Molecular Weight that was less readily biodegraded by indigenous microorganisms, and hence can persist in the environment as carcinogens.展开更多
Nanomaterials(NMs)have become an integral part of our daily life,and their extensive production will only increase with the increasing time.These NMs exhibit significant contrast regarding dimension,reaction,and struc...Nanomaterials(NMs)have become an integral part of our daily life,and their extensive production will only increase with the increasing time.These NMs exhibit significant contrast regarding dimension,reaction,and structure.The most important aspect of the NMs is that these can be easily manipulated and engineered to custom-suit different functions/industries.Owing to their dynamic nature,these NMs behave differently when introduced in any medium.In soil,the behavior of NMs is significantly controlled by the interactions of nanomaterials with soil phases.Although NMs are deemed beneficial for human-use,yet these also carry lethal effects.Moreover,there is a dearth of adequate research for the interactions among nanomaterials and soil physicochemical properties;their accumulation-dissolution dynamics in soil-plant systems;and their long term influence on soil health.Several NMs induce physiological stress when introduced inside the body.Thus,various researchers have devised green pathways for producing NMs,although their wide applicability is still questionable.Although the domain of nanotechnology is greatly explored,yet there remain several grey areas which need to be addressed for sustainable utilization of these unique materials in the benefit of humankind.展开更多
Introduction The health benefits of consuming aquatic organisms are clear,given their high protein count,low saturated fats,and low cholesterol content.Fish,in particular,contains valuable nutrients(e.g.,omega-3 polyu...Introduction The health benefits of consuming aquatic organisms are clear,given their high protein count,low saturated fats,and low cholesterol content.Fish,in particular,contains valuable nutrients(e.g.,omega-3 polyunsaturated fats),vitamins,essential elements,and is therefore considered an important part of a balanced human diet.China is a major seafood producer,accounting for 58%of global production in 2018(Crona et al.,2020).China is the largest seafood consuming country in the world,with consumption rates steadily increasing.Since the 1978 Chinese economic reform,the amount of seafood consumed per capita in China increased from 5 kg per capita in 1980 to 41 kg in 2015(Zhang et al.,2021).By 2030,the overall amount of fish consumption will likely exceed the amount of fish production in China.展开更多
We measured the concentrations of Cr,Fe,Ni,Cu,Zn,Cd,Pb and Hg,and the stable isotope ratios(δ^(13)C and δ^(15)N)in 87 fish samples within 12 economic fish species collected from the Dongting Lake,the second largest ...We measured the concentrations of Cr,Fe,Ni,Cu,Zn,Cd,Pb and Hg,and the stable isotope ratios(δ^(13)C and δ^(15)N)in 87 fish samples within 12 economic fish species collected from the Dongting Lake,the second largest freshwater lake in China.With few exceptions in concentration of Cr,most of fish species showed lower concentrations of the 8 metals than legislation thresholds.Piscivorous fishes had significantly higher values of δ^(15)N(possessing higher trophic level)and metal concentrations than planktivorous and herbivorous fishes.Moreover,demersal fishes showed higher concentrations of Cu,Zn,Cd and Pb than pelagic and benthopelagic fishes.We found positive correlations between concentrations of Fe,Pb and Hg and δ^(15)N ratio,confirming the biomagnification of the three metals through trophic transfer.In contrast,fishes showed clear growth dilution effect for Ni,Zn,Cu,Pb and Hg,indicated by the negative correlations between their concentrations and fish weight or length.Multiple regression analysis demonstrated that growth dilution and biomagnification effects simultaneously governed the metal concentrations in fish muscle,and the two effects'importance varied among different metals.The human health risk assessment indicated that all 8 metals gave target hazard quotient(THQ)values<1.0,i.e.,the estimated daily intake(EDI)of metals did not exceed the oral reference dose(Rf D),indicating a safe consumption of these fish species for consumer.Our study provides comprehensive approaches to better understand the determining processes and potential risk of heavy metals in freshwater lake fishes.展开更多
Chlorinated paraffins(CPs)present a complex mixture of congeners which are often analysed and assessed as short-,medium-and long-chain CPs,i.e.SSCCP(C10eC13),SMCCP(C14eC17)and SLCCP(C18).Their complexity makes the ch...Chlorinated paraffins(CPs)present a complex mixture of congeners which are often analysed and assessed as short-,medium-and long-chain CPs,i.e.SSCCP(C10eC13),SMCCP(C14eC17)and SLCCP(C18).Their complexity makes the chemical analysis challenging,in particular in terms of accurate quantification,but promising developments involving ultra-high resolution mass spectrometry have been presented lately.Most Arctic data exist for SCCPs,while LCCPs have not yet been studied in the Arctic.SSCCP concentrations in Arctic air often exceeded those of SMCCP,usually with a predominance of the most volatile C10 congeners,and of banned persistent organic pollutants(POPs),such as polychlorinated biphenyls(PCBs).The presence of SCCPs and MCCPs in Arctic air,as well as in the Antarctic and in the remote regions of the Tibetan plateau,provides evidence of their long-range transport including sufficient environmental persistence to reach the Arctic.Arctic vegetation accumulated SCCPs partly from air and partly through root uptake from soil,with consequences for the SCCP profile found in Arctic plants.No results have yet been reported for CPs in terrestrial Arctic animals.Results for freshwater sediment and fish confirmed the long-range transport of SCCPs and MCCPs and documented their bioaccumulation.Where additional PCB data were available,SPCB was usually higher than SSCCP in freshwater fish.Both SCCPs and MCCPs were widely present in marine Arctic biota(e.g.mussels,fish,seabirds,seals,whales,polar bears).In mussels and Atlantic cod,SMCCP concentrations exceeded those of SSCCP,while this was less clear for other marine species.Marine mammals and the long-lived Greenland shark roughly had SSCCP concentrations of 100e500 ng/g lipid weight,often dominated by C11 congeners.Biomagnification appeared to be more pronounced for SSCCP than for SMCCP,but more studies will be needed.Increasing SSCCP concentrations were observed in Arctic air and sediment over time,but not in beluga monitored since the 1980s.For both SCCPs and MCCPs,increasing concentrations over time have been shown in blue mussels and Atlantic cod at some,but not all stations.Indications exist of local sources of SCCPs in the Arctic,including Arctic settlements and research stations.In studies involving multiple locations,a general decrease of SCCP concentrations with increasing latitude or distance from point sources was observed as well as relatively more MCCPs at locations closer to potential CP sources.Monitoring of SCCPs and MCCPs has been initiated in some Arctic regions and will be important to assess the effect of recent regulations of SCCPs and the use of potential replacement chemicals.展开更多
Certain poly-and perfluoroalkyl substances(PFASs)exhibit significant bioaccumulation/biomagnification behaviors in ecosystems.PFASs,such as perfluorooctane sulfonate(PFOS),perfluorooctanoic acid(PFOA),perfluorohexanes...Certain poly-and perfluoroalkyl substances(PFASs)exhibit significant bioaccumulation/biomagnification behaviors in ecosystems.PFASs,such as perfluorooctane sulfonate(PFOS),perfluorooctanoic acid(PFOA),perfluorohexanesulfonic acid(PFHxS)and related precursors,have elicited attention from both public and national regulatory agencies,which has resulted in worldwide restrictions on their production and use.Apex predators occupy the top trophic positions in ecosystems and are most affected by the biomagnification behavior of PFASs.Meanwhile,the long lifespans of apex predators also lead to the high body burden of PFASs.The high body burden of PFASs might be linked to adverse health effects and even pose a potential threat to their reproduction.As seen in previous reviews of PFASs,knowledge is lacking between the current stage of the PFAS body burden and related effects in apex predators.This review summarized PFAS occurrence in global apex predators,including information on the geographic distribution,levels,profiles,and tissue distribution,and discussed the trophic transfer and ecotoxicity of PFASs.In the case where legacy PFASs were restricted under international convention,the occurrence of novel PFASs,such as 6:2 chlorinated polyfluorinated ether sulfonate(6:2 Cl-PFESA)and perfluoroethylcyclohexane sulfonate(PFECHS),in apex predators arose as an emerging issue.Future studies should develop an effective analytical method and focus on the toxicity and trophic transfer behavior of novel PFASs.展开更多
文摘Humans and animals can be exposed to Dioxins and Furans through ingestion of fatty food, skin contact, and breathing contaminated air. Resulting health problems include skin disease, immune problems, and cancers. Managing the release of these chemicals is therefore important. The Stockholm Convention on Persistent Organic Pollutants requires parties to adopt measures that reduce sources of these chemicals. Sierra Leone developed its National Implementation Plan (NIP) in 2008, in compliance with this requirement. However, no known further steps have been taken, particularly at community level. In 2013, the UNDP’s GEF/SGP funded a pilot project to manage the release of Dioxins and Furans from two dumpsites in Freetown, Sierra Leone. This work was sponsored with funds from that project. The work sought to delineate the exposure of communities within and around the Bormeh-Kingtom dumpsite (Kingtom, Kolleh town, Ascension town, Crab town, and Congo town) to the chemicals. The study considered sources of exposure, relative quantities generated per year, and the routes of exposure. This exposure study is a first step in managing the release from those sources. Enumerators deployed at the dumpsite every day, 7:00 AM to 6:00 PM, for three months, quantifying and recording source materials. The amount of source materials dumped per day informed calculation of Dioxin/Furan releases in grams toxicity equivalence per year. The results revealed a release of 128.914 g TEQ/year in air and residue. This implies that the communities are at high risk of inhalation and dermal exposure. Livestock, mainly pigs, are also exposed as they feed on the waste deposited in the dumpsite. Humans in turn feed on the livestock, a recipe for biomagnification. The project team has been working on developing Best Management Practices to suppress the release of the chemicals.
文摘Concentrations of selected heavy metals, nutrient elements and PAHs in farms and produce (cassava tubers and oil bean seeds) from 4-year-old crude oil impacted areas (Ekore and Uduvwoku) and a non-oil-impacted area (Okpe), all in Ughelli South Local Government Area, Delta State, Nigeria, were investigated to ascertain degree of risk posed. A random sampling design was chosen with three replications. Results obtained revealed significantly (P < 0.05) elevated (mg·kg<sup>-1</sup>) Cd (0.240, 0.140) and Cr (1.327, 3.122) in cassava samples for Ekore and Uduvwoku respectively in comparison to non-detectable amount for those of non-impacted source and exceeded set WHO limits of 0.1 and 0.05 mg·kg<sup>-1</sup> respectively. Although PAHs were low, oil spill increased available levels by factor of 2.5 and 5 for Ekore and Uduvwoku respectively. Again, Cd and Cr exceeded WHO limit for study impacted soils. Available N, P and K decreased (%) by 56.1, 28.5 and 2.4 for Ekore and 82.9, 39.9 and 45.5 for Uduvwoku Cassava samples. Nutrient profiling in oil bean revealed % reduction in avaliable N, P and K by 33.7, 47.7 and 57.9 and 28.9, 76.3 and 39.8 for Ekore and Uduvwoku samples respectively. For oil bean, Cd and Cr did not differ markedly between polluted samples but exceeded WHO limits. Other studied contaminants fell within limits. In soils, available N, P and K decreased (%) by 39.6, 79.1 and 27.4 for Ekore and 53, 88.1 and 45.5 for Uduvwoku samples. Low pH of 5.3 and 5.7 in Ekore and Uduvwoku respectively may increase the leachability of Cr into groundwater. Biopersistent Cd and Cr were found to biomagnify up the food chain and may impair major processes. Although PAHs were relatively low, their % composition was more of High Molecular Weight that was less readily biodegraded by indigenous microorganisms, and hence can persist in the environment as carcinogens.
文摘Nanomaterials(NMs)have become an integral part of our daily life,and their extensive production will only increase with the increasing time.These NMs exhibit significant contrast regarding dimension,reaction,and structure.The most important aspect of the NMs is that these can be easily manipulated and engineered to custom-suit different functions/industries.Owing to their dynamic nature,these NMs behave differently when introduced in any medium.In soil,the behavior of NMs is significantly controlled by the interactions of nanomaterials with soil phases.Although NMs are deemed beneficial for human-use,yet these also carry lethal effects.Moreover,there is a dearth of adequate research for the interactions among nanomaterials and soil physicochemical properties;their accumulation-dissolution dynamics in soil-plant systems;and their long term influence on soil health.Several NMs induce physiological stress when introduced inside the body.Thus,various researchers have devised green pathways for producing NMs,although their wide applicability is still questionable.Although the domain of nanotechnology is greatly explored,yet there remain several grey areas which need to be addressed for sustainable utilization of these unique materials in the benefit of humankind.
基金This work was supported by the Natural Sciences and Engineering Research Council of Canada,the Canadian Institutes of Health Research,and Alberta Health.
文摘Introduction The health benefits of consuming aquatic organisms are clear,given their high protein count,low saturated fats,and low cholesterol content.Fish,in particular,contains valuable nutrients(e.g.,omega-3 polyunsaturated fats),vitamins,essential elements,and is therefore considered an important part of a balanced human diet.China is a major seafood producer,accounting for 58%of global production in 2018(Crona et al.,2020).China is the largest seafood consuming country in the world,with consumption rates steadily increasing.Since the 1978 Chinese economic reform,the amount of seafood consumed per capita in China increased from 5 kg per capita in 1980 to 41 kg in 2015(Zhang et al.,2021).By 2030,the overall amount of fish consumption will likely exceed the amount of fish production in China.
基金supported by the National Natural Science Foundation of China(Nos.51709225,51622901,51939009)the Young Scientific Research Innovation Team Project of Xi’an University of Technology(No.104/256051715)。
文摘We measured the concentrations of Cr,Fe,Ni,Cu,Zn,Cd,Pb and Hg,and the stable isotope ratios(δ^(13)C and δ^(15)N)in 87 fish samples within 12 economic fish species collected from the Dongting Lake,the second largest freshwater lake in China.With few exceptions in concentration of Cr,most of fish species showed lower concentrations of the 8 metals than legislation thresholds.Piscivorous fishes had significantly higher values of δ^(15)N(possessing higher trophic level)and metal concentrations than planktivorous and herbivorous fishes.Moreover,demersal fishes showed higher concentrations of Cu,Zn,Cd and Pb than pelagic and benthopelagic fishes.We found positive correlations between concentrations of Fe,Pb and Hg and δ^(15)N ratio,confirming the biomagnification of the three metals through trophic transfer.In contrast,fishes showed clear growth dilution effect for Ni,Zn,Cu,Pb and Hg,indicated by the negative correlations between their concentrations and fish weight or length.Multiple regression analysis demonstrated that growth dilution and biomagnification effects simultaneously governed the metal concentrations in fish muscle,and the two effects'importance varied among different metals.The human health risk assessment indicated that all 8 metals gave target hazard quotient(THQ)values<1.0,i.e.,the estimated daily intake(EDI)of metals did not exceed the oral reference dose(Rf D),indicating a safe consumption of these fish species for consumer.Our study provides comprehensive approaches to better understand the determining processes and potential risk of heavy metals in freshwater lake fishes.
基金We acknowledge the Arctic Monitoring and Assessment Programme(AMAP)and the national programmes in the circumpolar countries for their funding and support of this work.We are grateful to Derek Muir,Cynthia de Wit and Simon Wilson for insightful discussions of the topic and to Tom Harner for providing SCCP data from the GAPS program.The northern communities in circumpolar regions are acknowledged for their cooperation and collection of biological samples that yielded the data reviewed here.The Danish contribution to this work was supported by the Danish Environmental Protection Agency,under the Cooperation for Environment in the Arctic(DANCEA),grants no.MST-112-191 and MST-113-00082.The National Laboratory for Environmental Testing(NLET)at Environment and Climate Change Canada is acknowledged for the analysis of air samples from Alert.
文摘Chlorinated paraffins(CPs)present a complex mixture of congeners which are often analysed and assessed as short-,medium-and long-chain CPs,i.e.SSCCP(C10eC13),SMCCP(C14eC17)and SLCCP(C18).Their complexity makes the chemical analysis challenging,in particular in terms of accurate quantification,but promising developments involving ultra-high resolution mass spectrometry have been presented lately.Most Arctic data exist for SCCPs,while LCCPs have not yet been studied in the Arctic.SSCCP concentrations in Arctic air often exceeded those of SMCCP,usually with a predominance of the most volatile C10 congeners,and of banned persistent organic pollutants(POPs),such as polychlorinated biphenyls(PCBs).The presence of SCCPs and MCCPs in Arctic air,as well as in the Antarctic and in the remote regions of the Tibetan plateau,provides evidence of their long-range transport including sufficient environmental persistence to reach the Arctic.Arctic vegetation accumulated SCCPs partly from air and partly through root uptake from soil,with consequences for the SCCP profile found in Arctic plants.No results have yet been reported for CPs in terrestrial Arctic animals.Results for freshwater sediment and fish confirmed the long-range transport of SCCPs and MCCPs and documented their bioaccumulation.Where additional PCB data were available,SPCB was usually higher than SSCCP in freshwater fish.Both SCCPs and MCCPs were widely present in marine Arctic biota(e.g.mussels,fish,seabirds,seals,whales,polar bears).In mussels and Atlantic cod,SMCCP concentrations exceeded those of SSCCP,while this was less clear for other marine species.Marine mammals and the long-lived Greenland shark roughly had SSCCP concentrations of 100e500 ng/g lipid weight,often dominated by C11 congeners.Biomagnification appeared to be more pronounced for SSCCP than for SMCCP,but more studies will be needed.Increasing SSCCP concentrations were observed in Arctic air and sediment over time,but not in beluga monitored since the 1980s.For both SCCPs and MCCPs,increasing concentrations over time have been shown in blue mussels and Atlantic cod at some,but not all stations.Indications exist of local sources of SCCPs in the Arctic,including Arctic settlements and research stations.In studies involving multiple locations,a general decrease of SCCP concentrations with increasing latitude or distance from point sources was observed as well as relatively more MCCPs at locations closer to potential CP sources.Monitoring of SCCPs and MCCPs has been initiated in some Arctic regions and will be important to assess the effect of recent regulations of SCCPs and the use of potential replacement chemicals.
基金supported by the National Natural Science Foundation of China(Nos.22022611,21906096)the National Key Research and Development Program of China(No.2020YFA0907500)the Youth Innovation Promotion Association of CAS(No.2018052).
文摘Certain poly-and perfluoroalkyl substances(PFASs)exhibit significant bioaccumulation/biomagnification behaviors in ecosystems.PFASs,such as perfluorooctane sulfonate(PFOS),perfluorooctanoic acid(PFOA),perfluorohexanesulfonic acid(PFHxS)and related precursors,have elicited attention from both public and national regulatory agencies,which has resulted in worldwide restrictions on their production and use.Apex predators occupy the top trophic positions in ecosystems and are most affected by the biomagnification behavior of PFASs.Meanwhile,the long lifespans of apex predators also lead to the high body burden of PFASs.The high body burden of PFASs might be linked to adverse health effects and even pose a potential threat to their reproduction.As seen in previous reviews of PFASs,knowledge is lacking between the current stage of the PFAS body burden and related effects in apex predators.This review summarized PFAS occurrence in global apex predators,including information on the geographic distribution,levels,profiles,and tissue distribution,and discussed the trophic transfer and ecotoxicity of PFASs.In the case where legacy PFASs were restricted under international convention,the occurrence of novel PFASs,such as 6:2 chlorinated polyfluorinated ether sulfonate(6:2 Cl-PFESA)and perfluoroethylcyclohexane sulfonate(PFECHS),in apex predators arose as an emerging issue.Future studies should develop an effective analytical method and focus on the toxicity and trophic transfer behavior of novel PFASs.
