The Problem with the Safety of Roundup Ready Soybeans.

• Author: Carman, Judy

The following is a critique of the methods used by Monsanto in its assessment that its product, Roundup Ready soybeans, also known as glyphosate-tolerant soybean line 40-3-2, is safe for human and animal consumption. The methods critiqued are those that appear in the "Full Assessment Report and Regulatory Impact Assessment," written by the Australian and New Zealand Food Authority (ANZFA) as the result of a request that these soybeans be permitted into Australia. The main role of this food authority is the protection of Australia's public health and safety. However, its other roles include the promotion of fair trade and consistency between domestic and international regulations. ANZFA rarely performs any safety testing of its own, but tends to rely on information obtained from elsewhere, including applicant companies.

The conclusion of this ANZFA document was that these soybeans are safe for human consumption. I have written this critique to highlight my concerns about that conclusion.

Roundup works by inhibiting an enzyme that is necessary for the plant to synthesise certain aromatic amino acids, killing the plant. The targeted enzyme is called 5-enolpyruvyl shikimate-3-phosphate synthetase, or EPSPS. The genetic modification in Roundup Ready soybeans involves incorporating a bacterial version of this enzyme (from Agrobacterium species, strain CP4) into the soybean plant, giving the soybean protection from Roundup. In this way, the soybeans and any weeds can be sprayed with Roundup, killing the weeds and leaving the soybeans.

Because of the way that this gene was incorporated into soybeans, several other DNA sequences are also present. They are the cauliflower mosaic virus 35S promoter, the EPSPS chloroplast transit protein (CTP) sequence from petunias and the 3' untranslated region of the nopaline synthetase gene (NOS3'). The ANZFA document completely omits discussion of the first and last of these and their proteins. For the petunia CTP, the applicant document states: "...it is generally accepted that the chloroplast transit peptides are rapidly degraded after cleavage in vivo by cellular proteases." That is, results from other general experiments are relied-upon and no evidence is provided that they have measured this to be the case in Roundup Ready soybeans.

The application states that the only new protein in these soybeans would be the EPSPS enzyme. They determined the ability of this EPSPS to be digested by setting up an in vitro...