Survey on Urinary Levels of Aflatoxins in Professionally Exposed Workers

Abstract

Feed mill workers may handle or process maize contaminated with aflatoxins (AFs). This condition may lead to an unacceptable intake of toxins deriving from occupational exposure. This study assessed the serological and urinary levels of AFs in workers exposed to potentially contaminated dusts in two mills. From March to April 2014, blood and urine samples were collected, on Monday and Friday morning of the same working week from 29 exposed workers and 30 non-exposed controls. AFs (M1, G2, G1, B1, B2) and aflatoxicol (AFOH) A were analyzed. Each subject filled in a questionnaire to evaluate potential food-borne exposures to mycotoxins. AFs contamination in environmental dust was measured in both plants. No serum sample was found to be positive. Seventy four percent of urine samples (73.7%) revealed AFM1 presence. AFM1 mean concentration was 0.035 and 0.027 ng/mL in exposed and non-exposed workers, respectively (p = 0.432); the concentration was slightly higher in Friday’s than in Monday’s samples, in exposed workers, 0.040 versus (vs.) 0.031 and non-exposed controls (0.030 vs. 0.024, p = 0.437). Environmental AFs contamination ranged from 7.2 to 125.4 µg/kg. The findings of this study reveal the presence of higher AFs concentration in exposed workers than in non-exposed controls, although these differences are to be considered consistent with random fluctuations.

Association between Urinary Levels of Aflatoxin and Consumption of Food Linked to Maize or Cow Milk or Dairy Products

“…and Heyndrickx and coll. found no contaminated samples and had similar analytical accuracy with the limit of detection (LoD) ranging from 0.0013 to 0.0025 ng/mL [15,16]; Solfrizzo reports a limit of quantification (LoQ) of 0.02 ng/mL, and only 6% of samples over the LoQ [17]; in the Reggio Emilia study [14], 33% of the samples were over 0.02 ng/mL. Only surveys from industrialized countries with a tropical climate have found similar proportions of contaminated samples, although concentration values of aflatoxins were about ten times lower than those observed in our study [8,[18][19][20][21][22]; similar levels of contamination have been observed only in the surveys conducted in Africa and Asia [23][24][25][26][27][28][29].…”

“…The study design and methods were described elsewhere [14]. Briefly, the study included only males, since the exposed workers were mostly males.…”

“…Our data come from a survey on food consumption and urine and serum aflatoxin levels designed to study potential occupational exposure at two mills in Northern Italy; that survey involved 30 exposed workers and 30 non-exposed controls [14]. Plant A is a large foodstuff plant that produces flour, compost, and pellet fuel, mostly derived from maize, and Plant B is a small cereal drying and sorting plant that processes mainly maize.…”

“…Detailed methods of extraction and detection of all the searched aflatoxins from urine and serum, as well as the most important validation parameters (relative standard deviation of repeatability, recovery, limit of detection (LoD)), trueness, and overall findings are reported elsewhere [14]. Since none of the serum samples was positive for any of the tested aflatoxins, and AFM1 was by far the most frequently found aflatoxin and the most clinically relevant [2], in the present work, analyses were restricted to AFM1 urinary levels.…”

“…In the spring of 2013 and 2014, the Reggio Emilia local health authority conducted a study to assess the risk of occupational exposure to aflatoxins at the two mills processing contaminated maize [14]. To conduct this study, a questionnaire on food consumption in the 96 h prior to urine and serum sample collection was administered both to exposed and non-exposed workers; urine and serum samples were then collected and tested for aflatoxin.…”