Author contributions
KPA, BJW, PLK, SOA and DJ, conceived of the study and oversaw implementation. KPA, FBO, SG and KB led data analysis. KPA, FBO, SG, AQ, and BJW led manuscript writing. PLK, SC, and DJ led exposure assessment teams. KPA, SOA, KAA, EBK SG, AGL and SK oversaw daily field operations. All authors contributed to data interpretation, manuscript preparation and review. All authors approved the final version of the manuscript.