Microbially Mediated Degradation of Common Pharmaceuticals and Personal Care Products in Soil Under Aerobic and Reduced Oxygen Conditions

Abstract

Biological degradation rates of estrogen compounds and common pharmaceutical and personal care products (PPCPs) were examined in soils with a long history of exposure to these compounds through wastewater effluent and in soil not previously exposed. Biological degradation rates over 14 days were compared under aerobic and anaerobic conditions. Estrogen compounds including estrone, 17β-estradiol, estriol, and 17α-ethinylestradiol exhibited rapid degradation by soil microorganisms in both aerobic and anaerobic conditions. Rapid degradation rates for estrone, estriol, and 17α-ethinylestradiol occurred in pre-exposed soil under aerobic conditions; half-lives calculated under these conditions were 0.6, 0.7, and 0.8 day, respectively. Unexposed soil showed similar or slightly longer halflives than pre-exposed soil under aerobic conditions. The exception was 17β-estradiol; in all treatments, degradation in unexposed soil resulted in a shorter halflife (2.1 versus 2.3 days). Anaerobic soils exhibited high biological degradation of estrogens as well. Half-lives of all estrogens ranged from 0.7 to 6.3 days in anaerobic soils. Triclosan degraded faster under aerobic conditions with half-lives of 5.9 and 8.9 days in exposed and unexposed soil. Under anaerobic conditions, triclosan half-lives were 15.3 days in unexposed and 28.8 days in exposed soil. Ibuprofen showed the least propensity toward biological degradation than other chemicals tested. Biological degradation of ibuprofen was only observed in unexposed soil; a half-life of 41.2 days was determined under anaerobic conditions and 121.9 days under aerobic conditions. Interestingly, unexposed soil exhibited a greater ability under anaerobic conditions to biologically degrade tested compounds than previously exposed soil.

Detection of pharmaceuticals and personal care products (PPCPs) in near-shore habitats of southern Lake Michigan

“…For example, aerobic conditions have been shown to foster biodegradation of PPCP compounds (Carr et al, 2011). Increased biodegradation due to greater oxygen availability may therefore explain negative correlations between percent oxygen saturation and total pharmaceutical abundance observed (Fig.…”

Current knowledge on the environmental fate, potential impact, and management of growth-promoting steroids used in the US beef cattle industry

“…According to the US Environmental Protection Agency (USEPA), each year almost 15 million Mg (16.5 million tn) of cattle manure are generated from feedlots (USEPA 2001). Assuming an average application rate of 56 Mg ha -1 (25 tn ac (Colucci et al 2001;Colucci and Topp 2002;Casey et al 2003Casey et al , 2004Lee et al 2003;Lai et al 2000;Das et al 2004;Carr et al 2011;Lucas and Jones 2006) and synthetic steroids in soil-water systems (Khan et al 2008). In general, the above studies found short half-life of these compounds in soil under aerobic conditions (table 3).…”

Occurrence, fate, and persistence of gemfibrozil in water and soil

“…Biodegradation experiments [23] were conducted using the two soil types described previously. Ten grams of sandy loam or silt loam soil was added to 40-ml glass vials.…”