Fate and transport of selected estrogen compounds in Hawaii soils: Effect of soil type and macropores Matteo D'Alessio a,b , Dharni Vasudevan c , Joseph Lichwa a , Sanjay K. Mohanty b,1 , Chittaranjan Ray a,b, ⁎ a Water Resources Research Center, University of Hawaii at Manoa, Honolulu, HI 96822, United States b Department of Civil and Environmental Engineering, University of Hawaii at Manoa, Honolulu, HI 96822, United States c Department of Chemistry, Bowdoin College, Brunswick, ME 04011, United States article info abstract Article history: Received 27 October 2013 Received in revised form 10 July 2014 Accepted 18 July 2014 Available online 25 July 2014 The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60–90 cm and 210–240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl 2 ), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β- estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii. © 2014 Elsevier B.V. All rights reserved. Keywords: 17β-estradiol Estrone Tropical soils Transport Recycled-water Macropores 1. Introduction Estrogen compounds in the environment are receiving significant attention due to their potential impact on freshwater organisms, ecosystems, and human health (Bolong et al., 2009; Corcoran et al., 2010). Estrogens naturally occur and are synthet- ically produced for use in oral contraceptives and hormonal therapy as well as in veterinary treatment of domestic and farm animals (Wise et al., 2011). Natural estrogens, E2 and E1 are excreted by women (2–12 and 3–20 μg/person/day, respective- ly) and female animals, as well as by men (E1 5 μg/person/day; see Ying et al., 2002). These compounds, at low concentrations, are capable of disrupting the endocrine systems of many organisms (Bolong et al., 2009). For example, exposure to estrogens at levels as low as 1 ng/L has been shown to cause feminization of male trout Journal of Contaminant Hydrology 166 (2014) 1–10 ⁎ Corresponding author at: Department of Civil and Environmental Engi- neering, University of Hawaii at Manoa, Honolulu, HI, 96822, United States. Tel.: +1 808 956 9652; fax: +1 808 956 5014. E-mail address: cray@hawaii.edu (C. Ray). 1 Current affiliation: Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, 94305, United States. http://dx.doi.org/10.1016/j.jconhyd.2014.07.006 0169-7722/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Journal of Contaminant Hydrology journal homepage: www.elsevier.com/locate/jconhyd