scope:

Introduction

The maximum allowable concentrations (MI-values) which will be presented below are intended to protect farm animals in sheds or pens, on pastures and in corrals from effects of thallium which would reduce their value.

Results of feeding experiments with farm animals are used for deriving the maximum allowable levels for thallium. The feeding experiments were conducted to determine the dose-effect relationship after oral ingestion.

Maximum levels can be derived for those farm animals with which such studies were performed. This is the case for beef bulls and meat-type hogs, sheep and fowl.

Of all farm animals especially those are affected by thallium which are kept outdoors part or most of the year.

According to present knowledge the thallium quantities mentioned in the following (Table 2) should not impair the health or performance of the farm animals nor should they cause any hazardous contamination of food products obtained from these animals. Therefore it can be assumed that consumption of such food products does not lead to any health impairment among humans. No combined effects of thallium with other heavy metals or other air pollutants have become known.

The MI-values are intended for the mentioned animal species provided the animals are fed and reared under the customary conditions. A short supply in minerals, trace elements, vitamins or other essential components of the fodder may increase the sensitivity of the animals to thallium. This is also true for the general state of health of the animals.