Environmental organic pollutants in hair samples from sport horses

Abstract

Background: Previous studies have shown high levels of persistent organic pollutants (POPs) and their risks in humans and domestic animals, especially in cats and dogs. However, studies regarding the levels of POPs in horses are limited. Objectives: To study the concentration of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organophosphate pesticides (OPs) in hair samples collected from 52 sport horses in Turkey and to investigate the possible relationship among current exposure situation, age and gender of horses. Study design: Original article. Methods: Hair samples were collected from 52 sport horses which were divided into three groups according to age: Group I: < 5 years (n = 17), Group II: 5-10 years (n = 16) and Group III: >10 years (n = 19). In addition to age, the samples were also analysed by location and gender. Thirty environmental pollutants (2 OPs, 7 OCPs, 15 PCBs and 6 PAHs) were analysed using a sensitive GC-MS method. Results: All samples contained a minimum of one pollutant, and 23 of the 30 measured pollutants were identified in at least one sample. Number of positive samples and concentrations of POPs were higher in Group 2 and Group 3 than Group I (p < 0.05). Females and males presented similar results. In terms of location, concentrations of almost all chemicals were higher in Sanliurfa than Ankara (p < 0.05). Main limitations: Feed, drinking water and the other related environmental samples were not analysed to evaluate the relationship between those sources and POPs levels in hair samples collected from sport horses. Conclusions: The concentration of POPs in the hair and other tissues of sports horses should be monitored periodically. To the best of our knowledge, this is the first report to investigate levels of the POPs in hair samples from sport horses in Turkey. Clinical relevance• The presence of POPs in animals could be a causative factor in a variety of diseases, including cancer, metabolic disorders, immune suppression, growth failures, cardiovascular diseases and congenital abnormalities, even at very low concentrations.• In the present study, the levels of POPs in horse hair were generally higher than previous studies conducted in humans and other animals. These findings may indicate the extent of environmental contamination as well as the importance of POPs as an external factor responsible for health problems in sport horses.• In the future, determining any relationships between the levels of POPs in biological fluids and race performance of sport horses could be worthwhile.

Review of scientific literature on available methods of assessing organochlorine pesticides in the environment

“…Large matrix effects have been reported by the US Department of Agriculture in residue analysis at low spike concentration (with 50–150 % recoveries) which cannot be entirely removed by cleanup procedures (Dana Ayu Mustofa et al, 2022). Unusual recoveries of 200.54 % from hair samples [ 72 ], 15–144 % from owl feathers [ 73 ], 5, 9, 36 % [ 74 ], 172.6, 169.3, 180.9, 140.7, and 167.3 %, which was thought to be mostly caused by the significant variances between the soils [ 75 ], and 69–140, 8.2–41.6 from soil [ 76 ], have been recorded. Several recovery techniques are reported ( Table 1 ), such as procedural blank, spiked blank, spiked sample, and surrogate recovery among others.…”

“…Afterwards, the temperature was increased by 4 °C/min to 240 °C and then by 60 °C/min to 300 °C” [ 413 ] Hunan Hair 14 0.011–1.38 Int std: 83-180 GC-MS: “The column temperature was initially held at 70 °C for 2 min, raised to 150 °C at the rate of 25 °C/min, then to 200 °C at the rate of 3 °C/min, and to 280 at a rate of 8C, held for 10 min, finally to 300 °C at the rate of 100 °C/min, held at final temperature for 5 min. Total analysis time was 47.067 min” [ 289 ] Hair, liver Liver: 0.01–0.11; hair: 0.14–1.4 Liver:0.1–0.50; hair: 0.1–10 Liver: 74–119; hair: 61- 12 <20 % GC-QqQ-MS/MS [ 414 ] Hair of wild cat 10 0.01–0.5 94–110 <10 GC-ECD: Splitless, “100 °C (1 min), 10 °C/min to 240 °C (1 min), 3 °C/min to 260 °C (1 min), 20 °C/min to 300 °C (10 min)” [ 415 ] Hair 7 0.01–0.1 0.02–0.38 2.51–200.54 GC-MS: “The starting temperature was 60 °C, held for 1 min, ramped to190°Cat40 °C/min, ramped to 280°Cat5°C/min, held for2 minutes, ramped to 290°Cat10 °C/min and held for 5 min” [ 72 ] a = values not converted. …”