## 1 Introduction  
Organochlorine pesticides (OCPs) are ubiquitous, resistant, and persistent compounds, and one of the key sources of pollution that contribute to environmental degradation and pose a potential health risk to humans and animals [1; 2]. For many decades, OCPs were used to control pests and pathogens in agricultural production [3; 4]. Due to their negative impact on the environment and human health, OCPs were banned by the Stockholm Convention on Persistent Organic Pollutants, an international environmental treaty signed in 2001 [5]. Despite this ban, OCP residues are still identified in various environments, food products, and in human and animal bodies [6; 7; 8]. Organochlorine pesticides are characterized by low selectivity and exert toxic effects not only on target pests, but also on non-target animal species and humans [9; 10]. These compounds are harmful not only to the individuals who are directly exposed, but also to consumers of contaminated food [11; 12; 13]. The uptake of contaminants by plants is often the first step in the process of their accumulation in human and animal food chains [7; 14; 15]. Organochlorine pesticides contain the active ingredients 1,1,1-Trichloro-bis-2,2 [4-chlorophenyl]-ethane (DDT, sold under the Azotox trademark in Poland) and \(\gamma\)-hexachlorocyclohex (\(\gamma\)-HCH, lindane) [16]. In Poland, the use of pesticides containing DDT and \(\gamma\)-HCH was banned in 1976 and 1988, respectively. Residues of DDT, its metabolites (dichlorodiphenyldichloroethylene, DDE, and dichlorodiphenyldichloroethane, DDD), and \(\gamma\)-HCH are still present in soil and can be assimilated by crop plants. These residues have been identified in many plant- and animal-based foods [11; 17; 18]. Organochlorine pesticides are highly resistant to environmental degradation [19; 20]. These organic pollutants are highly persistent in the natural environment, and their half-life in soils can last up to several decades [21]. Pesticide contamination reduces both the biodiversity and functions of soil-dwelling microorganisms [22; 23], which slows down the degradation of residual pollutants. The accumulation of OCPs in the soil environment can be attributed to both point source pollution (industrial emissions, processed waste, and wastewater) and non-point source pollution (wind and precipitation), where the latter plays the key role in transporting these contaminants over long distances [24; 25]. Numerous environmental factors (soil quality, history of pesticide use, climate) can contribute to the persistence or degradation of OCP residues [4; 26; 27]. Remediation treatments aiming to improve soil properties through the addition of soil amendments such as organic matter considerably retard the biodegradation of OCPs because these compounds bind to dissolved organic carbon [28]. Soils abundant in organic matter absorb more organic pollutants because hydrophobic compounds have affinity for selected organic matter fractions [29; 30]. Organochlorine pesticides are compounds with very high adsorption coefficients, which implies that they can be strongly bound to soil particles [23]. Prolonged exposure to OCPs leads to their bioaccumulation in food chains [3; 7; 31]. Their residues can be transferred to livestock through contaminated feed or pesticides used to control external parasites [32; 33]. Organochlorine pesticides are lipophilic, and they can accumulate in the adipose tissue of animals [31]. Elevated concentrations of these toxic compounds have been found in organs such as the liver and the kidneys. As a rich source of nutrients, meat and bone meal (MBM) derived from slaughterhouse waste is used as fertilizer [34; 35; 36] or feed [37], thus contributing to the spread of organochlorine contaminants in the agricultural environment [38].