INTRODUCTIONOver the last years, the presence of chemical residues, especially antibiotics and pesticides in food of animal origin has become a public health issue. The world population is commonly exposed to drug residues through microdoses present in food, resulting in a variety of serious health effects such as hypersensitivity and anaphylactic shock, especially in children, pregnant women and the elderly, anemia, diarrhea and kidney problems, imbalance of intestinal flora and teratogenicity, besides ototoxicity and problems in fetal bone development (NASCIMENTO et al, 2001; MARTIN, 2011;TROMBETE et al, 2014). Moreover, the indiscriminate use of these substances promotes antimicrobial resistance, which can lead to antibiotic therapy unsuccessfully (WHITE & MCDERMOTT, 2001 Furthermore, these chemical residues are resistant to conventional heat treatment used for manufacturing pasteurized milk (72 o C), so industrial technologies are considered ineffective to eliminate these drugs residues (TIAN et al., 2016).In addition, fermented products like cheese and yogurt have its processes closely affected by the presence of antibiotic residues in raw material, as these usually inhibit partially or totally the growth of dairy cultures (starter cultures), damaging the sensory and structural characteristics of those milk products (FONSECA et al, 2009).The presence of antibiotic residues in milk may occur for many reasons, including the indiscriminate use of drugs for treatment of herd diseases, by not disposing contaminated milk and due to prolonged or excessive dosages of drugs (TROMBETE et al, 2014). Milk contamination by antimicrobials residues can still be possibly originating from the intentional addition, performed in order to inhibit undesirable bacterial growth, thus covering the deficiency in the hygienic quality of milk (PONTES NETTO et al, 2005). Therefore, monitoring the use of these substances is essential to ensure food security and to provide adequate guidance of the drugs used by farmers and milk producers (TOLENTINO et al, 2005). Consequently, it is necessary to implement preventive measures to notice the presence of these chemical residues in milk consumed by the general population.This study searched to verify the possible presence of antibiotic residues in pasteurized and unpasteurized milk, produced and marketed in the microregion of Capanema, State of Paraná, Brazil, through qualitative screening methods for detection of four different groups of drugs, β-lactams, tetracyclines, quinolones and sulfonamides, to map the status of the chemical milk quality in respect of contamination by antibiotic residues.
MATERIALS AND METHODS
β-lactam and tetracyclic researchA collection of 100 pasteurized milk samples of 13 different brands collected from many different commercial establishments in the city of Realeza, state of Paraná, during the period from April 2015 to August 2015 were analyzed. Choice of brands was based on information provided by the supermarkets, according to the milk consumption by the popula...