Publications by authors named "Daniel C Lehman"

As part of the Integrated Atmospheric Deposition Network, precipitation ( = 207) and air ( = 60) from five sites and water samples ( = 87) from all five Great Lakes were collected in 2021-2023 and analyzed for 41 per- and polyfluoroalkyl substances (PFAS). These measurements were combined with other available data to estimate the mass budget for four representative compounds, PFBA, PFBS, PFOS, and PFOA for the basin. The median ΣPFAS concentrations in precipitation across the five sites ranged between 2.

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Although diet is an important route of exposure for brominated flame retardants (BFRs), little is known of their presence in US food. Therefore, we purchased meat, fish, and dairy product samples ( = 72) in Bloomington, IN, from 3 stores representing national retail chains at different price levels. Composite samples ( = 42) were analyzed for polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), novel BFRs (NBFRs), and dechlorane plus (DP).

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Thirty-five polybrominated diphenyl ethers (PBDEs) and eight other alternative flame retardants were measured in air samples (vapor plus particles) collected at six sites near the North American Great Lakes between 2005 and 2019 as part of the Integrated Atmospheric Deposition Network (IADN). These data were analyzed using a multiple linear regression model to determine spatial and temporal trends. Overall, the levels of flame retardants remain significantly higher in urban sites compared to rural and remote sites except for pentabromoethylbenzene (PBEB), hexabromobenzene (HBB), and total Dechlorane Plus (ΣDP).

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We define here "temporal environmental hysteresis" as the time lag between when a pollutant's input to the environment stops and when its concentration in the environment drops to some desired fraction of its maximum concentration. The goal of this paper is to investigate temporal environmental hysteresis for polybrominated diphenyl ethers (PBDEs), which were widely used as flame retardants in consumer goods. These compounds were taken off the North American market in two steps: At the end of 2004, the so-called Penta-BDE and Octa-BDE products were withdrawn, and at the end of 2013, the Deca-BDE product was also discontinued.

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Dechlorane Plus (DP) is a chlorinated flame retardant manufactured only in Niagara Falls, New York and in Huai'an, China. To determine if the environmental levels of this compound were changing significantly, we measured the long-term temporal trends of its concentrations near the Great Lakes between 2005 and 2015 using air (vapor + particle phase) samples (N = 1047) and precipitation samples (N = 449). We used a multiple linear regression model of DP concentrations to isolate the variabilities due to sampling date and population near the sampling site.

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Environmental measurement programs are often undertaken with the assumption that measurements at a given location will be comparable to others that would be observed at the same time in the immediate vicinity, but this assumption has seldom been tested. This paper does so. We discuss here the precision of atmospheric concentration measurements of persistent organic pollutants (POPs) near the North American Great Lakes-measurements that we have been conducting since 1994.

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