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River temperatures affect water quality, power plant cooling, and freshwater ecosystems. Stream temperature models that treat river reaches and reservoirs as well‐mixed segments do not capture thermal stratification in reservoirs. To account for the effects of reservoir stratification on downstream water temperatures, we developed a two‐layer stratified reservoir module, which was integrated into the River Basin Model (RBM) to simulate river temperature across a river network with multiple large thermally stratified reservoirs. To evaluate the performance of this model configuration compared to RBM without thermally stratified reservoirs, we simulated river temperature in the Tennessee River Basin in the southeastern United States. We simulated land surface hydrologic fluxes using the Variable Infiltration Capacity (VIC) model and routed runoff using the river routing model RVIC. The two‐layer model configuration reduced the bias in simulated summer river temperature from 6.7 to −1.2 °C downstream of a reservoir with a residence time of 92 days and from 3.0 to −0.7 °C downstream of a reservoir with a residence time of 8 days. Improvement in fall and winter, when reservoirs tend to be well mixed, is minimal. RBM with the two‐layer module also captured the observed longitudinal river temperature variation downstream of a reservoir, with cool temperatures immediately downstream of the reservoir and gradual warming of the river as it flows downstream. Incorporating a simple stratified reservoir module into RBM improves model performance and increases the ability to apply the river temperature model to large basins with multiple large reservoirs.

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Lead exposure is associated with a wide range of adverse effects on human health. The principal exposure route in the general population is through the diet. In this study, we estimate the dietary lead intake and associated health risks among the residents of Guangzhou, China. Data on lead concentrations were derived from the food safety risk monitoring system, which included 6339 samples from 27 food categories collected in 2014–2017. Food consumption data were taken from a 2011 dietary survey of 2960 Guangzhou residents from 998 households. Dietary lead intake was estimated by age group (3–6, 7–17, 18–59, and ≥60 years), and relevant health risks were assessed using the margin of exposure (MOE) method. The mean and 95th percentiles (P95) of dietary lead intake were respectively 0.7466 and 2.4525 μg/kg body weight per day for preschool children aged 3–6 years; 0.4739 and 1.5522 μg/kg bw/day for school children aged 7–17 years; 0.3759 and 1.1832 μg/kg bw/day for adults aged 18–59 years; and 0.4031 and 1.3589 μg/kg bw/day for adults aged ≥60 years. The MOE value was less than 1 for preschool children at the mean exposure level and for all age groups at the P95 exposure level. Rice and its products, leafy vegetables, and wheat flour and its products were found to be the primary food sources of lead exposure. Our findings suggest that the health risk from dietary lead exposure is low for Guangzhou residents overall, but that young children and consumers of certain foods may be at increased risk. Continued efforts are needed to reduce the dietary lead exposure in Guangzhou.