Mycotoxins feed contamination in a dairy farm – potential implications for milk contamination and workers' exposure in a One Health approach

Abstract

BACKGROUND: Dairy farming feed can be contaminated with mycotoxins, affecting animals' health and milk quality. Dairy farming is also prone to occupational exposure to mycotoxins, and feed is recognized as a source of contamination in the workplace. An exploratory study was developed in a dairy farm located in Portugal intending to assess the mycotoxins present in the feed. RESULTS: All the samples analyzed presented contamination by at least two mycotoxins and up to a maximum of 13 mycotoxins in the same sample. Zearalenone (ZEA) was detected in all the samples (n = 10) followed by deoxynivalenol (DON), which was reported in eight samples, and ochratoxin A (OTA), reported in five samples.CONCLUSION: The results point to the possible contamination of milk by several mycotoxins and raise the possibility of occupational exposure to mycotoxins due to feed contamination. An adequate One Health approach for dairy production should address these issues through effective preventive actions such as avoiding the use of feed contaminated with mycotoxins. This represents an important challenge due to climate change. It requires proper attention and accurate management measures.

Occupational Exposure to Mycotoxins—Different Sampling Strategies Telling a Common Story Regarding Occupational Studies Performed in Portugal (2012–2020)

“…High exposure to organic dust containing mycotoxins, secondary toxic metabolites produced by fungi, can occur during the development of several working routine activities, such as storage work, loading, handling, or milling contaminated materials (e.g., grain, waste, and feed) in different types of industries (e.g., brewing, bakeries), and others such as caring for animals in animal husbandry settings [1][2][3][4][5][6][7][8]. Despite this occupational exposure has been demonstrated in previous research work [9][10][11][12][13][14][15][16][17][18][19], exposure assessment is not routinely performed and mycotoxins are still not recognized as an occupational risk factor present in several workplaces [20].…”

“…More recently, in a study developed in one dairy farm, all the feed samples analyzed presented contamination by at least two mycotoxins and up to a maximum of 13 mycotoxins in the same sample. Zearalenone (ZEA) was detected in all the samples (n = 10, 0.60-266 ng/g) followed by DON (n = 8, <1-197 ng/g), and Ochratoxin A (OTA) (n = 5, <0.13-4.53 ng/g) [14]. Therefore, and in line with the results previously found in swine, feed can be the principal contamination source for mycotoxins in all occupational environments where animals need to be fed [13].…”

“…In this, and in previous studies developed in animal production and food processing facilities, besides an occupational health concern, there is also a food safety concern present-justifying a holistic approach to prevent all these concerns. An adequate One Health approach should address this perspective through effective preventive actions such as avoiding the use of contaminated raw materials (e.g., feed, flours) [14].…”

Mycotoxin Exposure and Related Diseases

“…Animals can be exposed to mycotoxins through the consumption of contaminated feed, subsequently entering into the food chain, and thus constituting a source of exposure to humans [5]. Regarding human exposure, in addition to the dietary source, the workplace environment can also represent an exposure source.…”

“…Regarding human exposure, in addition to the dietary source, the workplace environment can also represent an exposure source. Dust containing mycotoxins is released during regular tasks involving high exposure to organic dust, such as storage work, loading, handling, or milling contaminated materials (grain, waste, and feed), and other tasks such as caring for animals in animal husbandry settings [5][6][7][8][9][10][11][12][13][14][15].…”