Reevalvacija ocene tveganja za zdravje na primeru dezinfekcije pitne vode s klorom : magistrsko delo

Goličnik, Blaž (avtor), Poljšak, Borut (mentor)

Uvod: Dezinfekcija pitne vode predstavlja eno najpomembnejših javno zdravstvenih pridobitev v zadnjem stoletju. Pojavil pa se je nov javno zdravstveni problem, in sicer povečano tveganje zbolevanja za rakom ter reproduktivni, razvojni in drugi učinki na zdravje zaradi stranskih produktov dezinfekcije. Trihalometani in haloocetne kisline sta glavni skupini stranskih produktov dezinfekcije, kloroform pa glavni predstavnik trihalometanov. V svetu je bilo opravljenih precej ocen tveganja zaradi prisotnosti stranskih produktov dezinfekcije v pitni vodi, v Sloveniji pa tovrstna raziskava še ni bila opravljena. Namen: Namen je bil izdelati oceno tveganja za zdravje ljudi zaradi prisotnosti kloroforma v pitni vodi vodovodov celjske zdravstvene regije. Pri tem smo v oceno tveganja vključili vse poti vnosa kloroforma preko pitne vode. Upoštevali smo tudi prispevek povišanih koncentracij trihalometanov v vodi za tuširanje. Metode dela: Izdelali smo oceno tveganja za kloroform na primeru oskrbovalnih območij v celjski zdravstveni regiji. Na podlagi razpoložljivih podatkov smo ovrednotili vse faze ocene tveganja: identifikacijo škodljivega dejavnika, oceno odziva na dozo in oceno izpostavljenosti ter določili tveganje ob različnih scenarijih izpostavljenosti po mednarodno uveljavljeni metodologiji. Rezultati: Skupno tveganje je bilo, ne glede na izpostavljeno populacijo, pri veliki večini uporabnikov pitne vode iz javnih sistemov oskrbe s pitno vodo (> 90 %) sprejemljivo (nižje od sprejemljivega v primeru suma kemikalije na rakotvornost po WHO: 1 : 10-5. Pri oskrbovalnem območju z največjo povprečno koncentracijo kloroforma v pitni vodi je bilo skupno tveganje pri vseh populacijah višje od tega kriterija. Najmanjši doprinos k skupnemu tveganju je zaradi zaužitja. Največja skupna tveganja smo izračunali za populacijo otrok od 1,5 do 5 let. Skupno tveganje za to populacijo pri oskrbovalnem območju z najvišjo povprečno koncentracijo kloroforma 2,2-krat (upoštevajoč IUR) ali 9,9-krat (upoštevajoč FV) presega sprejemljivo tveganje po WHO. Razprava in zaključek: Ocenjujemo, da je tveganje za zdravje zaradi kloroforma za veliko večino uporabnikov pitne vode v celjski zdravstveni regiji sprejemljivo. Iz izračunov tveganj na osnovi mejne vrednosti in na osnovi najvišje povprečne koncentracije kloroforma v celjski zdravstveni regiji je razvidno, da so na prikazanih primerih tveganja presežena. Po našem mnenju bi bilo treba mejno vrednost za vsoto trihalometanov v Sloveniji znižati.

• Jezik: Slovenski jezik
• Ključne besede: stranski produkti dezinfekcije, kloroform, pitna voda, celjska zdravstvena regija, ocena tveganja
• Vrsta gradiva: Magistrsko delo/naloga
• Organizacija: ZF - Zdravstvena fakulteta
• Leto izida: 2019
• PID: 20.500.12556/RUL-109103
• COBISS.SI-ID: 5667435
• Datum objave v RUL: 22.08.2019

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Reevaluation of a health risk assessment on the case of disinfection of drinking water with chlorine : master thesis

Izvleček

Introduction: Disinfection of drinking water is one of the most important public health improvements in the last century. But with general disinfection based on chlorine, a new public health problem emerged, namely an increased risk of cancer, reproductive, developmental and other health effects due to disinfection by products. Trihalomethanes in haloacetic acids are the main groups of disinfection by products and chloroform is the main representative of trihalomethanes. Considerable number of risk assessments have been made in the world regarding disinfection by products in drinking water, but in Slovenia such a study has not yet been carried out. Purpose: The purpose was to assess the risk to human health due to the presence of chloroform in the drinking water systems in the Celje health region. All possible pathways of chloroform entering human body were included in the risk assessment. We also took into account the contribution of trihalomethanes concentrations in water intended for showering. Methods: We made a risk assessment for chloroform in the case of water supply areas in the Celje health region. On the basis of the available data, we evaluated all the stages of the risk assessment: identification of the harmful factor, dose response assessment, exposure assessment and risk determination under different exposure scenarios according to the internationally established methodology. Results: The total risk was, regardless of the exposed population, acceptable (lower than acceptable in the case of a chemical suspicion of carcinogenicity according to the WHO: 1 : 10-5) for the vast majority of drinking water users from Celje health region public drinking water supply systems (> 90 %). For drinking water supply zone with the highest average chloroform concentration in drinking water, the overall risk for all populations was higher than this criterion. The smallest contribution to the overall risk is due to ingestion. The highest overall risk was calculated for the population of 1,5–5 years. The total risk for this population in supply zone with a maximum average chloroform concentration exceeds the acceptable risk 2,2 times (taking into account IUR) or 9,9 times (taking into account FV). Discussion and conclusion: We estimate that the health risk due to chloroform is acceptable for the vast majority of drinking water users in the Celje health region. From calculations of risks based on limit value (100 ?g/L) and on the basis of the highest average concentration of chloroform in the Celje health region, it is evident that the risks are exceeded. In our opinion, the limit value for the total amount of trihalomethanes in Slovenia should be reduced.

• Ključne besede: disinfection by products, chloroform, drinking water, Celje health region, risk assessment