TY - JOUR
T1 - Human health risks for Legionella and Mycobacterium avium complex (MAC) from potable and non-potable uses of roof-harvested rainwater
AU - Hamilton, Kerry A.
AU - Ahmed, Warish
AU - Toze, Simon
AU - Haas, Charles N.
N1 - Funding Information:
This work was supported by a Fulbright-CSIRO Postgraduate scholarship sponsored by the Australian-American Fulbright Commission. The authors are grateful to rainwater study participants for providing survey information used in this work and for CSIRO staff Dr. Jatinder Sidhu, Leonie Hodgers, Andrew Palmer, Kylie Smith, and Pradip Gyawali for their contributions to the original pathogen quantification study used in this risk assessment.
Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2017
Y1 - 2017
N2 - A quantitative microbial risk assessment (QMRA) of opportunistic pathogens Legionella pneumophila (LP) and Mycobacterium avium complex (MAC) was undertaken for various uses of roof-harvested rainwater (RHRW) reported in Queensland, Australia to identify appropriate usages and guide risk management practices. Risks from inhalation of aerosols due to showering, swimming in pools topped up with RHRW, use of a garden hose, car washing, and toilet flushing with RHRW were considered for LP while both ingestion (drinking, produce consumption, and accidental ingestion from various activities) and inhalation risks were considered for MAC. The drinking water route of exposure presented the greatest risks due to cervical lymphadenitis and disseminated infection health endpoints for children and immune-compromised populations, respectively. It is therefore not recommended that these populations consume untreated rainwater. LP risks were up to 6 orders of magnitude higher than MAC risks for the inhalation route of exposure for all scenarios. Both inhalation and ingestion QMRA simulations support that while drinking, showering, and garden hosing with RHRW may present the highest risks, car washing and clothes washing could constitute appropriate uses of RHRW for all populations, and toilet flushing and consumption of lettuce irrigation with RHRW would be appropriate for non- immune-compromised populations.
AB - A quantitative microbial risk assessment (QMRA) of opportunistic pathogens Legionella pneumophila (LP) and Mycobacterium avium complex (MAC) was undertaken for various uses of roof-harvested rainwater (RHRW) reported in Queensland, Australia to identify appropriate usages and guide risk management practices. Risks from inhalation of aerosols due to showering, swimming in pools topped up with RHRW, use of a garden hose, car washing, and toilet flushing with RHRW were considered for LP while both ingestion (drinking, produce consumption, and accidental ingestion from various activities) and inhalation risks were considered for MAC. The drinking water route of exposure presented the greatest risks due to cervical lymphadenitis and disseminated infection health endpoints for children and immune-compromised populations, respectively. It is therefore not recommended that these populations consume untreated rainwater. LP risks were up to 6 orders of magnitude higher than MAC risks for the inhalation route of exposure for all scenarios. Both inhalation and ingestion QMRA simulations support that while drinking, showering, and garden hosing with RHRW may present the highest risks, car washing and clothes washing could constitute appropriate uses of RHRW for all populations, and toilet flushing and consumption of lettuce irrigation with RHRW would be appropriate for non- immune-compromised populations.
KW - Legionella pneumophila
KW - Mycobacterium avium complex
KW - Opportunistic pathogens
KW - Quantitative microbial risk assessment (QMRA)
KW - Roof-harvested rainwater
UR - http://www.scopus.com/inward/record.url?scp=85019025502&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85019025502&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2017.04.004
DO - 10.1016/j.watres.2017.04.004
M3 - Article
C2 - 28500949
AN - SCOPUS:85019025502
SN - 0043-1354
VL - 119
SP - 288
EP - 303
JO - Water Research
JF - Water Research
ER -