Distribution and concentrations of pharmaceutical and personal care products (PPCPs) within cattails (Typha latifolia) as function of exposure time.

CORCORAN, SHAWNA; METCALFE, CHRIS; SULTANA, TAMANA; AMÉ, M. VALERIA; MENONE, MIRTA L

Toronto

Congreso; SETAC North America 40th Annual Meeting; 2019

SETAC

The passive uptake of organic contaminants such as PPCP by plants is well documented. Uptake is often quantified and reported as concentration ratios between whole plants or specific plant compartments (e.g. roots, shoots, leaves, fruit) and the exposure media (e.g. soil, air water). The ratios may also be normalized to the amount water transpired by the plant or to lipid content of the plant tissue. However, there have been relatively few studies that have investigated the changes in concentrations among the various plant tissue compartments over time. Using hydroponically grown cattails (Typha latifolia) exposed to four PPCPs (carbamazepine, fluoxetine, gemfibrozil, trichlosan) at environmentally relevant concentrations near 20 ug/L, the uptake and distribution of these compounds within the plants were evaluated at several time periods over a 42 day growing period. Thirty-six plants of uniform size were selected, eighteen exposed to the target PPCPs and eighteen untreated. Two unplanted, unexposed controls were also used. A nutrient solution containing the target compounds was used to replenish water lost to transpiration and maintain a consistent exposure environment (semi-static exposure bioassay). Root zone samples were collected over time to determine the average exposure concentration. Whole plants were harvested at days 7, 14, 21, 28, 35 and 42 days. Concentrations of PPCPs in the exposure solution and various plant tissues were determined by direct injection LC-MSMS or after extraction, concentration and cleanup. Carbamazepine, fluoxetine, gemfibrozil and triclosan were detected in all underwater tissues (roots, rhizome, etc.) and above water tissues, except gemfibrozil which was not detected in shoots. Carbamazepine concentrations were highest in the upper leaves in the plants exposed for the longest time. Concentrations in the below water tissues were 30-40 times lower than the upper leaves and did not vary significantly with time. Above water tissue concentrations for fluoxetine were highest in the lower leaves and similar to the concentrations in the below water tissues. Triclosan concentrations were greatest in the roots and were about 50 higher than those found in the leaves. Overall, the results show that the root uptake, translocation and distribution within the plant tissues varies with the physical chemical properties of PPCP and longer exposures result in higher leaf concentrations for those compounds that are translocated from root to shoot. For compounds that are readily translocated from roots to shoots, the large differences in tissue concentrations could have important implications in risk assessment and biomonitoring applications.