Extract from a report from *)


Trace analysis laboratory

321, avenue Jean Jaurès – F-69362 Lyon Codex 07

CARSO Assay: CAR/03-0987 – July 4th, 2003

Customer: Perlite Institute, order dated 04/22/2003


For several years there has been an increasing concern over the possibilities presence of dioxin in minerals because of the possibility of making its way into the food chain.

The issue first appeared in about 1998 in the US and was focused on dioxin levels in anticaking products used in animal feeds and feed ingredients and produced from ball clays. The US FDA continued to follow the matter and issued a Guidance for Industry that called for caution on the part of industry with regard to all mined-clays in order to remove a potential source of dioxins in the human food chain.

This was based upon analyses concluded by EPA that unexpectedly indicated the presence of dioxin in many mined clays. The guidance was updated to include non-clay anti-caking products with an advisory statement that “companies not use any clay or non-clay anti-caking products contaminated with dioxin in animal feed and feed ingredients.” The guidance was base upon analyses conducted by EPA

This was followed in the year 2000 by an addendum to NTP’s ninth Annual Report on Carcinogens which listed dioxin (TCDD) as a known human carcinogen.

In Europe, the EU Commission in August, 2003 adopted Directive 2002/32/EC establish maximum dioxin limits for several feed materials and compound feeding stuffs in animal feeds. The limit for several minerals is 1.0 ng WHO-TEQ/kg. In 2004, it is anticipated that the Directive will be expanded to include dioxin-like PCBs. As a result of the following data which was provided by the Perlite Institute the European Commission, Perlite has been exempted from this directive.

ProductCountryDioxin Conc. 1Dioxin Conc. 2
Perlite, expandedDenmark0.115 30.115 3
Perlite, expandedFrance0.020 30.170 4
Perlite, expandedGermany0 40.070 4
Perlite, expandedGreece0.330 40.380 4
Perlite, expandedItaly0.010 30.080 4
Perlite, expandedGreece0.190 40.240 4
1 assuming non-detect = 0
2 upper bound, assuming non-detect = limit of detection of the test laboratory
3 ng I-TEQ/kg
4 WHO-TEQ ng/kg

Some of the values were reported using the I-TEQ convention and some were reported using the WHO-TEQ convention. The resulting differences due to the differing reporting procedures are slight.

PCDD/PCDFs results:

Sample IDCARSO IDNg TEQ- WHO/kg InitialNg TEQ- WHO/kg Dried matterNg TEQ- WHO/kg Dried matter
1. Perlite, expanded aggregate03-120990.0880.0890-078
2. Perlite, fine ore03-103090.1960.1970.173
3. Perlite, filter aid03-116820.0820.0830.073
4. Perlite, coarse ore03-11662-30.0740.0740.065

“DIOXIN-LIKE” PCBs results:

Sample IDCARSO IDNg TEQ- WHO/kg Dried matter Ng TEQ- WHO/kg Dried matter
1. Perlite, expanded aggregate03-120990.0240.021
2. Perlite, fine ore03-103090.0090.008
3. Perlite, filter aid03-116820.0070.006
4. Perlite, coarse ore03-116620.0060.005

The overall toxicity of the sample, conventionally expressed as the I-TEQ of 2,3,7,8-TCDD, is calculated on the basis of the amounts of the 17 PCDD/PCDFs and the 12 “dioxin-like” toxic congeners timed their toxicity factor from WHO (World Health Organization)

The results show all Perlites tested are significantly below current and proposed limits, and supports that conclusion that Perlite and Perlite products are not contaminated with dioxin or dioxin-like PCBs.

*) extract made and re-written by Nordisk Perlite ApS, DK-3400 Hillerød. A copy of the full report from CARSO Institute can be handed out by request. In such a case please contact us.