Stable work is arduous, repetitive and requires a lot of energy expenditure, according to researchers, who warn that the air quality can present health risks.
Polish researchers who evaluated the working conditions of staff engaged in tending horses concluded that stables were workplaces with considerable risks of triggering “unfavourable health effects”.
The Lublin-based researchers, from the University of Life Sciences and the Institute of Rural Health, set out to assess the level of exposure to air pollution in a stable and estimate the work-load of workers tending to the animals.
Bożena Nowakowicz-Dębek and her colleagues, whose findings have been published in the Annals of Agricultural and Environmental Medicine, found that stable air was “considerably contaminated” with microorganisms, some of which posed biological hazards.
The study team carried out their research work in the winter in a stable that housed 40 racehorses.
Air samples were collected and analysed to determine the number of bacteria and fungi present, as well as the number of aerobic mesophilic and thermophilic bacteria.
Measurements of total dust concentration in the air were also performed. They also evaluated the energy expenditure, physical load, and type of movements performed by the workers.
The researchers found that the workers tending horses performed their activities using 90 percent of the daily working time as an effective period of work.
“Work with tending horses is very arduous,” they reported, evidenced by the total energy expenditure across an eight-hour shift of 2649 kilocalories, or 11,099.3 kilojoules. The research team also noted the “mediocre monotony” of the movements
They found that the mean concentration of the total number of bacteria in the air in the stable exceeded what was considered a safe value for workers.
Most sampling points recorded excessive concentrations of mesophilic bacteria and fungi exceeded the recommended values, while the numbers of thermophilic bacteria were in accordance with recommendations, despite their high levels.
Dust levels were found to be lower than the maximum allowable concentration of particulate organic plant and animal origin in the working environment, defined at 4 milligrams per cubic metre.
“The presented study confirms that work with tending animals is very heavy, which is evidenced by the energy expenditure,” Nowakowicz-Dębek and her colleagues reported. “The noxiousness of the work is exacerbated by the conditions in which it is performed.”
They described the air present in rooms housing animals as a diverse mixture containing – together with organic dust – microorganisms and their toxins.
Of particular concern is the finer dust that can be inhaled to the gas exchange surfaces within the lungs.
“This fraction has been considered as the indicator of health risk in horses,” they said.
“Keeping horses in the contaminated air of the stable leads to recurrent obstruction of the airways. It has been estimated that in 33–80 percent of stables there occurs in horses non-septic inflammation of the airways, with a lower tolerance of physical effort, which disqualifies many animals from participation in training or competitions.”
In the current study, Brevibacterium spp., Arcanobacterium, and Microbacterium spp. were most frequently identified, as well as agents classified as Group 2 of hazards, such as Staphylococcus aureus, Actinomyces pyogenes and Streptococcus spp.
A considerable diversity of microflora was observed. In all stables, Aspergillus spp., Penicillium spp., Eurotium spp., Monilia spp. and Alternaria alternate were identified.
The research team suggested that biomarkers of exposure of workers engaged in tending horses should be identified.
“An increase in the recreational use of horses brings about the risk of occurrence of respiratory system problems in workers engaged in tending the animals,” they said.
“The conducted studies indicate that it is necessary to search for new methods of evaluation of exposure in order to effectively prevent these problems.”
Nowakowicz-Dębek was joined in the research by Halina Pawlak, Łukasz Wlazło, Izabela Kuna-Broniowska, Hanna Bis-Wencel, Agnieszka Buczaj and Piotr Maksym.
Nowakowicz-Dębek B, Pawlak H, Wlazło Ł, Kuna-Broniowska I, Bis-Wencel H, Buczaj A, Maksym P. Evaluation of working conditions of workers engaged in tending horses. Ann Agric Environ Med. 2014; 21(4): 718–722. doi: 10.5604/12321966.1129921