San<span style="font-family:Verdana;">itation by-products (i.e. greywater, human urine and toilet compost</span><span style="font-family:Verdana;">) reuse for agriculture presents...San<span style="font-family:Verdana;">itation by-products (i.e. greywater, human urine and toilet compost</span><span style="font-family:Verdana;">) reuse for agriculture presents an opportunity to enhance food security while overcoming water scarcity and fertilizers issues in developing countries. However, the risks to health from farmers and consumers’ exposure to pathogenic micro-organisms persistent in sanitation by-products has hindered their popularity in these regions. This study was conducted to apply a quantitative microbial risk assessment to estimate the annual risk probability of </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"> infection associated with these sanitation by-products reuse for lettuce production and explore options for health risk reduction. Risk was performed a M</span><span style="font-family:Verdana;">onte Carlo simulation for farmers and consumers. The exposure rout</span><span style="font-family:Verdana;">es were contaminated soil ingestion, urine/greywater/compost ingestion and lettuce consumption without washing. Results showed that the annual infection risks of </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"> through ingestion contaminated soil associated with urine and compost were typical scenario: 9.04 × <img src="Edit_23087809-01c6-443a-a5a4-d700e0119b4a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> per-person-per-year (pppy) and 2.97 × <img src="Edit_3581c627-e1c8-4520-b34c-6dbfdf3f6935.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy, respectively, are higher than the WHO benchmark (≤1.0 × <img src="Edit_56f7f561-c618-4f34-a1e9-e0595c06186a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy). Conversely, those contaminated from greywater were 6.83 × <img src="Edit_cdb77922-3d6a-4ffa-be33-acd591505adc.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:;" "=""><span style="font-family:Verdana;"> ppp</span><span style="font-family:Verdana;">y are meet the WHO benchmark. On the other hand, annual risks</span><span style="font-family:Verdana;"> through lettuce consumption fertilized with urine (1.20 × <img src="Edit_02bf163d-b72b-43be-962e-9ca62fca3b5a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) were less than the risks from compost (6.20 × <img src="Edit_8f5035d9-ba8c-44d3-ba04-fa8210f0ba5a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) and greywater (7.76 × <img src="Edit_fe2dc136-a861-4617-80af-e01dc2df7a73.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy). Moreover, the annual risks</span></span><span style="font-family:Verdana;"> of</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> infection from greywater ingestion (1.77 × <img src="Edit_a71ed737-298d-42f5-9678-ba257374b364.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup> <span style="font-family:Verdana;">pppy) exhibits </span></span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">much higher risk than th</span><span style="font-family:Verdana;">at</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> urine ingestion (6.20 × <img src="Edit_9f57f54f-2be2-4464-ae07-33d40b2f4790.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) approximately two orders of magnitude, and which are higher than the WHO tolerable limit of risk. The risk assessment outcomes of using sanitati</span></span><span style="font-family:Verdana;">on by-products to lettuce production should be promoted with pro</span><span style="font-family:Verdana;">per awareness of the risk by farmers and consumers.</span>展开更多
As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in re...As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in recent years,people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water,especially the pathogenic microorganisms in it.In this study,the water quality and microorganisms of the Old Summer Palace,a landscape water body with reclaimed water as the only replenishment water source,were tracked through long-term dynamic monitoring.And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment(QMRA).It was found that the concentration of indicator microorganisms Enterococcus(ENT),Escherichia coli(EC)and Fecal coliform(FC)generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow.The concentrations of indicator microorganisms were higher in summer and autumn than those in spring.And there was a positive correlation between the concentration of indicator microorganisms and COD.Further research suggested that increased concentration of indicator microorganisms also led to increased health risks,which were more than 30%higher in other areas of the park than the water inlet area and required special attention.In addition,(water)surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks.展开更多
Reclaimed water utilization provides an effective way to alleviate water shortage.However,the residual pathogens in the recycled water like Legionella,could be spread into the air as aerosols through water-to-air tran...Reclaimed water utilization provides an effective way to alleviate water shortage.However,the residual pathogens in the recycled water like Legionella,could be spread into the air as aerosols through water-to-air transmission process.Inhaling the aerosols by the people nearby increases their susceptibility to diseases.For estimating the health risks associated with the potential exposure of airborne Legionella emitted from the urban use of reclaimed water in China,nationwide questionnaire was designed to investigate the exposure habits of Chinese population in different scenarios.Quantitative microbial risk assessment(QMRA)served as the suitable explanatory tool to estimate the risk.The results indicated that annual infection probability of populations exposed to Legionella for three scenarios,0.0764(95%CI:0.0032−0.6880)for road cleaning,1.0000(95%CI:0.1883−1.0000)for greenfield irrigation,0.9981(95%CI:0.0784−1.0000)for landscape fountain,were markedly higher than the threshold recommended by WHO(10^(−4) per person per year(pppy))according to the concentration distribution of Legionella in the reclaimed water.An age-,educational background-,region-and gender-specific data in annual infection probability also showed different tendencies for some subpopulations.This study provides some detailed information on the health risks from the water reuse in China and will be useful to promote the safe application of reclaimed water in water-deficient areas.展开更多
文摘San<span style="font-family:Verdana;">itation by-products (i.e. greywater, human urine and toilet compost</span><span style="font-family:Verdana;">) reuse for agriculture presents an opportunity to enhance food security while overcoming water scarcity and fertilizers issues in developing countries. However, the risks to health from farmers and consumers’ exposure to pathogenic micro-organisms persistent in sanitation by-products has hindered their popularity in these regions. This study was conducted to apply a quantitative microbial risk assessment to estimate the annual risk probability of </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"> infection associated with these sanitation by-products reuse for lettuce production and explore options for health risk reduction. Risk was performed a M</span><span style="font-family:Verdana;">onte Carlo simulation for farmers and consumers. The exposure rout</span><span style="font-family:Verdana;">es were contaminated soil ingestion, urine/greywater/compost ingestion and lettuce consumption without washing. Results showed that the annual infection risks of </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"> through ingestion contaminated soil associated with urine and compost were typical scenario: 9.04 × <img src="Edit_23087809-01c6-443a-a5a4-d700e0119b4a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> per-person-per-year (pppy) and 2.97 × <img src="Edit_3581c627-e1c8-4520-b34c-6dbfdf3f6935.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy, respectively, are higher than the WHO benchmark (≤1.0 × <img src="Edit_56f7f561-c618-4f34-a1e9-e0595c06186a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy). Conversely, those contaminated from greywater were 6.83 × <img src="Edit_cdb77922-3d6a-4ffa-be33-acd591505adc.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:;" "=""><span style="font-family:Verdana;"> ppp</span><span style="font-family:Verdana;">y are meet the WHO benchmark. On the other hand, annual risks</span><span style="font-family:Verdana;"> through lettuce consumption fertilized with urine (1.20 × <img src="Edit_02bf163d-b72b-43be-962e-9ca62fca3b5a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) were less than the risks from compost (6.20 × <img src="Edit_8f5035d9-ba8c-44d3-ba04-fa8210f0ba5a.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) and greywater (7.76 × <img src="Edit_fe2dc136-a861-4617-80af-e01dc2df7a73.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy). Moreover, the annual risks</span></span><span style="font-family:Verdana;"> of</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> infection from greywater ingestion (1.77 × <img src="Edit_a71ed737-298d-42f5-9678-ba257374b364.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup> <span style="font-family:Verdana;">pppy) exhibits </span></span><span style="font-family:Verdana;">a </span><span style="font-family:Verdana;">much higher risk than th</span><span style="font-family:Verdana;">at</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> urine ingestion (6.20 × <img src="Edit_9f57f54f-2be2-4464-ae07-33d40b2f4790.png" alt="" /></span><sup><span style="font-family:Verdana;"></span></sup><span style="font-family:Verdana;"> pppy) approximately two orders of magnitude, and which are higher than the WHO tolerable limit of risk. The risk assessment outcomes of using sanitati</span></span><span style="font-family:Verdana;">on by-products to lettuce production should be promoted with pro</span><span style="font-family:Verdana;">per awareness of the risk by farmers and consumers.</span>
基金supported by the National Natural Science Foundation of China(Nos.52070192 and 51778618).
文摘As an important means to solve water shortage,reclaimed water has been widely used for landscape water supply.However,with the emergence of large-scale epidemic diseases such as SARS,avian influenza and COVID-19 in recent years,people are increasingly concerned about the public health safety of reclaimed water discharged into landscape water,especially the pathogenic microorganisms in it.In this study,the water quality and microorganisms of the Old Summer Palace,a landscape water body with reclaimed water as the only replenishment water source,were tracked through long-term dynamic monitoring.And the health risks of indicator microorganisms were analyzed using Quantitative Microbial Risk Assessment(QMRA).It was found that the concentration of indicator microorganisms Enterococcus(ENT),Escherichia coli(EC)and Fecal coliform(FC)generally showed an upward trend along the direction of water flow and increased by more than 0.6 log at the end of the flow.The concentrations of indicator microorganisms were higher in summer and autumn than those in spring.And there was a positive correlation between the concentration of indicator microorganisms and COD.Further research suggested that increased concentration of indicator microorganisms also led to increased health risks,which were more than 30%higher in other areas of the park than the water inlet area and required special attention.In addition,(water)surface operation exposure pathway had much higher health risks than other pathways and people in related occupations were advised to take precautions to reduce the risks.
基金supported by the Major Water Project of China(No.2017ZX07103)the National Key R&D Program of China(2018YFC0406300).
文摘Reclaimed water utilization provides an effective way to alleviate water shortage.However,the residual pathogens in the recycled water like Legionella,could be spread into the air as aerosols through water-to-air transmission process.Inhaling the aerosols by the people nearby increases their susceptibility to diseases.For estimating the health risks associated with the potential exposure of airborne Legionella emitted from the urban use of reclaimed water in China,nationwide questionnaire was designed to investigate the exposure habits of Chinese population in different scenarios.Quantitative microbial risk assessment(QMRA)served as the suitable explanatory tool to estimate the risk.The results indicated that annual infection probability of populations exposed to Legionella for three scenarios,0.0764(95%CI:0.0032−0.6880)for road cleaning,1.0000(95%CI:0.1883−1.0000)for greenfield irrigation,0.9981(95%CI:0.0784−1.0000)for landscape fountain,were markedly higher than the threshold recommended by WHO(10^(−4) per person per year(pppy))according to the concentration distribution of Legionella in the reclaimed water.An age-,educational background-,region-and gender-specific data in annual infection probability also showed different tendencies for some subpopulations.This study provides some detailed information on the health risks from the water reuse in China and will be useful to promote the safe application of reclaimed water in water-deficient areas.
