Higher Levels of Aflatoxin M1 Contamination and Poorer Composition of Milk Supplied by Informal Milk Marketing Chains in Pakistan.

Naveed Aslam,Muhammad Ishaq,Ann Cowling,David Mcgill,Muhammad Yasin Tipu,Peter Wynn,Hassan Mahmood Warriach

doi:10.3390/toxins8120347

Abstract

The present study was conducted to observe the seasonal variation in aflatoxin M1 and nutritional quality of milk along informal marketing chains. Milk samples (485) were collected from three different chains over a period of one year. The average concentrations of aflatoxin M1 during the autumn and monsoon seasons (2.60 and 2.59 ppb) were found to be significantly higher (standard error of the difference, SED = 0.21: p = 0.003) than in the summer (1.93 ppb). The percentage of added water in milk was significantly lower (SED = 1.54: p < 0.001) in summer (18.59%) than in the monsoon season (26.39%). There was a significantly different (SED = 2.38: p < 0.001) mean percentage of water added by farmers (6.23%), small collectors (14.97%), large collectors (27.96%) and retailers (34.52%). This was reflected in changes in milk quality along the marketing chain. There was no difference (p = 0.178) in concentration of aflatoxin M1 in milk collected from the farmers (2.12 ppb), small collectors (2.23 ppb), large collectors (2.36 ppb) and retailers (2.58 ppb). The high levels of contamination found in this study, which exceed the standards set by European Union (0.05 ppb) and USFDA (0.5 ppb), demand radical intervention by regulatory authorities and mass awareness of the consequences for consumer health and safety.

Highlights

IntroductionA significant proportion of food and food products worldwide is affected by mycotoxins (fungal secondary metabolites) each year [1]
A significant proportion of food and food products worldwide is affected by mycotoxins each year [1]
A continuous decline in milk quality with respect to solids not fat (SNF), fat, protein and lactose content, and an increase in Aflatoxin M1 (AFM1), was observed as milk passed along the milk supply chains from farmers to retailers

Summary

Introduction

A significant proportion of food and food products worldwide is affected by mycotoxins (fungal secondary metabolites) each year [1]. Among these mycotoxins, aflatoxins (AFs) are the most toxic compounds. Aflatoxin M1 (AFM1), produced as a result of hydroxylation of AFB1 [3], is detected in the milk of animals and humans after the ingestion of feed contaminated with AFB1 [5]. AFB1 is dependent on the cytochrome P450 group of enzymes for its conversion to 8, 9 AFB1 epoxide, resulting in its carcinogenicity and acute cytotoxicity [6]. AFM1 has toxic effects without the need for metabolic activation [3]

Methods

Results

Discussion

Conclusion