Mouse model, exposure, and breeding paradigm
F0 C57BL/6j mice (n=16, 8 weeks of age) were purchased from Jackson Laboratory (Bar Harbor, Maine). Mice were maintained on a 12:12 light/dark cycle and had ad libitum access to the standard lab diet Envigo 2018 (18% protein) chow and tap water (tested at 1ppb iAs) until the beginning of the exposure. All animals were individually housed until breeding. Tap water from the University of Minnesota was treated with iAsIII (Millipore Sigma) at the following doses: 10 ppb, 245 ppb, and 2300 ppb. Water quality and arsenic concentrations were tested at Tri-City/ William Lloyd Analytical Lab (Bloomington, MN). Female mice from the F1 generation (n=4 per treatment), were used to produce the F2 generation. Mice used for glucose tolerance were selected at random for the initial 8 week measurement and remained enrolled for glucose tolerance at the 25 and 38 week time points throughout the study. The following quantity of mice survived the 40 weeks without health confounding factors, and were used for behavior testing and weekly body weight; (F1 1 ppb: male n= 10, female n=7; F1 10 ppb: male n=9, female n = 4; F1 245 ppb: male n= 8, female n=4; F1 2300 ppb: male n=7, female n=7; F2 1 ppb: male n=10, female n=8; F2 10 ppb: male n=10, female n=12; F2 245 ppb: male n=10, female n=11; F2 2300: male n=6, female n=5). Mice were treated humanely and in accordance with the Guidelines for the Care and Use of Laboratory Animals (Institute of Laboratory Animal Resources, 1996). The study protocol was approved by the University of Minnesota Institutional Animal Care and Use Committee (IACUC).