Yes, mycotoxin tissue distribution, bioaccumulation, carry-over, persistence, and transference, as well as mycotoxin toxicokinetics (absorption, distribution, metabolism, and excretion) is highly variable depending upon the specific mold species, specific mycotoxin metabolite, the contaminated plant or animal food, the human host’s immunological response, and the biological sample tested (serum/plasma, urine, feces, sputum, breast milk, amniotic fluid).
Studies show rapid absorption, distribution, metabolism and excretion of many mycotoxins metabolites, within hours to a few days, however 100% excretion, from a dose-dependent exposure, is not achieved. Rather, studies show highly variable percentages of urinary excretion. Mycotoxin excretion is based on mycotoxin exposure in a dose-dependent and time-dependent manner. Tissue persistence occurs when mycotoxins bioaccumulate in lipophilic (fat-loving) tissues.
Animal studies in pigs, chicken, cows/cow milk, sheep, fish, turkey, and geese and duck (and their eggs), show mycotoxin excretion for anywhere from 4-72 days after mycotoxin exposure. Some mycotoxins are thermally stable, and demonstrate several levels of bioaccumulation. Some mycotoxins have high carry-over from mycotoxin-contaminated animal feed into animal tissues, milk, and eggs. Carry-over refers to transfer from feed to edible tissues in food-producing animals.
Urine biomarkers reflect day-to-day variations in mycotoxin intake which can explain intraindividual variability (within an individual) and why biomonitoring with serial measurements over time may be more predictive of a person’s “normative” mycotoxin status (Lopez et al., 2020, Toxins, 12, 147).
Differing mycotoxin results may be explained by intra-individual variability and temporal variability and may not necessarily reflect an overall “worsening” of “toxic” status. Clinical correlation is required to assess for objective and subjective signs and symptoms of improving/worsening status.
A comparative study of human urinary mycotoxin excretion patterns suggests considerable inter-individual (between individuals) and intra-individual variability in urinary mycotoxin excretion, this study estimated exposures to calculate “probable daily intakes” (PDI) and “tolerable daily intakes” (Gerding et al., 2015, Mycotoxin Research, 31, 127-136).
Exposure studies for mycotoxins typically combine contamination data (of agricultural and environmental mycotoxins) with consumption data (from national dietary surveys). Despite the high sensitivity of mycotoxin extraction and detection methods by LC/MS chromatography, and population contamination and consumption data, inter-individual and intra-individual variability needs to be characterized better (Marin et al., 2013, Food and Chem Toxicol, 60, 218-237).
