Applicability of the Charm II system for monitoring antibiotic residues in manure-based composts S.I. Kwon a , G. Owens b , Y.S. Ok c , D.B. Lee a , W.-T. Jeon d , J.G. Kim e , K.-R. Kim e,⇑ a Climate Change & Agroecology Division, Department of Agricultural Environment, National Academy of Agricultural Science, RDA, 150 Suin-ro, Kwonsun-gu, Suwon 441-707, Republic of Korea b Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia c Department of Biological Environment, Kangwon National University, Chuncheon 200-701, Republic of Korea d Crop Environment Research Division, Nation Institute of Crop Science, Suwon 441-857, Korea e Division of Environmental Science and Ecological Engineering, College of Life and Environmental Sciences, Korea University, 1-5 Anam-dong Seongbuk-gu, 136-701 Seoul, Republic of Korea article info Article history: Received 8 February 2010 Accepted 11 August 2010 Available online 23 September 2010 abstract The effluence of veterinary antibiotics (VAs) to aquatic and terrestrial environments is of concern due to the potential adverse effects on human health, such as the production of antibiotic resistant bacteria. One of the main pathways for antibiotics to enter the environment is via the application of manure and/or manure-based composts as an alternative organic fertilizer to agricultural lands. While a wide diversity of manure-based composts are produced in Korea, there is currently no regulatory guideline for VA resi- dues. Hence, monitoring and limiting the concentration of VA residues in manure and/or manure-based composts prior to application to the lands is important to mitigate any environmental burden. The current study was conducted to examine the applicability of the Charm II antibiotic test system for monitoring tet- racyclines, sulfonamides and macrolides in manure-based composts. The Charm II system was a highly reproducible method for determining whether VA residue concentrations in manure-based compost exceeded specific guideline values. A wide range of manure-based composts and liquid fertilizers com- mercially available in Korea were examined using the Charm II system to monitor the residues of the tar- get VAs. For this, the guideline concentrations of VA residues (0.8 mg kg 1 for tetracyclines, 0.2 mg kg 1 for sulfonamides, and 0.1 mg kg 1 for macrolides) stated in ‘Official Standard of Feeds’ under the ‘Control of Livestock and Fish Feed Act’ in Korea were adopted to establish control points. Of the 70 compost sam- ples examined 12 exceeded 0.8 mg kg 1 for tetracyclines and 21 exceeded 0.2 mg kg 1 for sulfonamides. Of the 25 liquid fertilizer samples examined most samples exceeded these prospective guidelines. Ó 2010 Elsevier Ltd. All rights reserved. 1. Introduction A wide range of veterinary antibiotics (VAs) are used in live- stock farming for disease control and as feed additives for animal growth promotion (Aust et al., 2008). However, since pharmaceu- tical antibiotics are not significantly bioaccumulated (Thiele- Bruhn, 2003), a high proportion of these VAs are excreted via urine and feces as the non-metabolized parent compounds (Halling- Sorensen et al., 2001; Arikan et al., 2009). For instance, orally ap- plied tetracyclines were rapidly excreted via feces and urine, and significant amounts (72%) of the active ingredient initially dis- pensed were recovered (Winckler and Grafe, 2001). Such VAs embedded in animal waste are of concern due to application of manure to agricultural lands as an alternative to organic fertilizer and the subsequent effluence of the VAs into the surrounding envi- ronment. Since VAs are often found to be recalcitrant after excre- tion (Bouwman and Reus, 1994; Dolliver et al., 2008a), VAs can spread into the ground and surface water by infiltration and runoff, respectively (Burkhardt et al., 2005; Kay et al., 2005; Avisar et al., 2009a,b). Elevated levels of antibiotics in the environment contrib- uted to the development of antibiotic resistant microbial popula- tions (Witte, 1998) and even very low quantities of antibiotics encouraged the occurrence of antibiotic resistant bacteria (Khacha- tourians, 1998; Hirsch et al., 1999; Boxall et al., 2003). In addition, some of these antibiotics may even cause serious allergies or may be toxic to humans (Patterson et al., 1995; Kumar et al., 2005). In 2005, the total amount of VAs used in Korea was estimated at around 1500 tons which was four times more than the UK and 15 times more than Denmark (KFDA, 2006) and hence the VA residues in livestock manure in Korea are expected to be relatively high. In addition, animal manures in Korea are usually used for compost pro- duction, consequently resulting in relatively high proportions of VA residues being embedded in manure-based compost that can be 0956-053X/$ - see front matter Ó 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.wasman.2010.08.018 ⇑ Corresponding author. Tel.: +82 2 3474 3060; fax: +82 2 953 0737. E-mail address: kimkr419@korea.ac.kr (K.-R. Kim). Waste Management 31 (2011) 39–44 Contents lists available at ScienceDirect Waste Management journal homepage: www.elsevier.com/locate/wasman