Neuropathy and chloracne induced by 3,5,6-trichloropyridin-2-ol sodium:Report of three cases

BACKGROUND Chloracne is a rare skin condition that is caused by systemic exposure to halogenated aromatic compounds.The main characteristic of chloracne is blackhead,and in severe cases,it can be accompanied by systemic symptoms.Sodium 3,5,6-trichloropyridin-2-ol(STCP)is a necessary precursor compound for the production of chlorpyrifos and triclopyr,which are extensively used as a pesticide and herbicide,respectively.STCP is also a chlorophenol that has been associated with chloracne.STCP poisoning could induce mild myelin sheath damage.We herein report three cases with chloracne due to exposure to STCP.CASE SUMMARY Three young men,aged 29,33,and 26 years,respectively,in the same workplace had polymorphic skin lesions,characterized mainly by comedones and cysts,and one of them also had acne like lesions in the genital area.These clinical manifestations appeared when they were exposed to STCP for 3 d,1 wk,and 2 wk,respectively.Among them,polyneuropathy and liver damage occurred.We performed dermoscopy and clinical and laboratory tests on these patients.Additionally,histopathology was used for further diagnosis in the serious patient.These patients were diagnosed with chloracne and separated from STCP.The patients were prescribed oral viaminate capsules,topical adapalene gel,and regular hematologic follow-up for aspartate transaminase and lipids.They are still under follow-up.There was no new lesions and the laboratory tests returned to normal in two patients.Pigmentation and shallow scars remained in the original areas of papules.However,in the most serious patient,new papules still appeared intermittently.All these remind us that the treatment of chloracne caused by STCP is difficult,and we should attach great importance to this new compound related with the neuropathy and chloracne.CONCLUSION STCP is becoming a new chemical product to induce chloracne,which should attract the attention of all medical professionals,especially dermatologists.Due to the lack of knowledge on the new chemical,the diagnosis of chloracne cannot be made in time.Chloracne still deserves our attention.

Atmospheric dispersion of chemical,biological,and radiological hazardous pollutants:Informing risk assessment for public safety

Modern society is confronted with emerging threats from chemical,biological,and radiological(CBR)hazardous substances,which are intensively utilized in the chemical,medical,and energy industries.The atmospheric dis-persion of released CBR hazardous pollutants can influence a large percentage of the population owing to their rapid process with extensive spatial coverage.It is important to comprehensively understand the behaviors of the released CBR pollutants in the atmosphere to fully evaluate the risks and protect public safety.In this study,we reviewed the advancements in the atmospheric transport of CBR pollutants,including the urban atmospheric boundary layer,unique concepts,and models for CBR pollutants.We underlined the development of innovative methodologies(e.g.,inverse estimation and data assimilation methods)for the atmospheric transport of acciden-tally released CBR pollutants to reduce uncertainties in emissions and accumulated errors during dispersion by combining numerical models with monitoring data.Finally,we introduced progress in quantitative risk assess-ment,including exposure assessment and dose-response relationships for CBR hazardous pollutants.A framework,source,assimilation,fundamentals,exposure,and risk(SAFER),has been proposed to integrate the key compo-nents in the risk assessment of airborne CBR hazardous pollutants.These methods and models can contribute to effective risk preparedness,prevention,evidence-based policymaking,and emergency response to airborne CBR pollutants.