Are these claims substantiated?
Of course, the answer to this question depends on what you mean by anti-science or anti-technology. If the scientific model upon which genetic engineering is based is faulty, is it anti-science to oppose it?
To this, I would answer: yes and no. It is "anti-science" in the strict sense that it is against a particular scientific model and is committed to providing a new one. But in this sense, all science is anti-science! All science is based on the principle that premises are open to revision and in need of aligning with evidence supported through inductive experimentation. Einstein was "anti-science" in this sense for promoting a relativistic physical model that flew in the face of the established theory mechanics. But his new model was also a better description of the phenomena.
For this reason, concern about genetic engineering is COMPLETELY consistent with the scientific spirit. And the fact is that we have ample evidence to show the inadequacy of the model upon which genetic engineering is based.
IF each gene coded for a single protein did not interact in any way with the expression or regulation of neighboring genes, and IF the resulting genetically engineered organism was therefore IDENTICAL except with respect to this single changed trait, and IF the changed trait could have no impact on the behavior of the organism in ecosystems, then genetic engineers would have reason to mock those claiming that genetic engineering is dangerous.
The problem is that none of these assumptions are at all true. The fact is that most genes are in networks. Putting new genes into existing networks changes the existing relationships between the other genes. Unexpected consequences are the rule and the amount of chemical and physiological studies needed to establish equivalence in every aspect would be astronomical. Being required to provide such evidence would put biotech companies out of business. Why did the anti-freeze gene from a flounder, inserted into a salmon's DNA, cause the salmon to grow at a faster rate? Until genetic engineers can predict this sort of thing, what they are doing should not even be called "engineering." And yet, even though these sorts of unanticipated effects emerge, as long as they are marketable, they will be marketed. Supersalmon [sic] is now up for approval in Canada and the USA.
This image shows how the "code illusion", the assumption that each gene code for one property, is a computer metaphor that has no place in a scientific understanding of the interconnectivity of genetic systems. The image below shows networks of interaction between genes in an Aribidopsis plant (source: Thum, et al. 2008).
It is also impossible to predict how a genetically engineered organism will interact with the other living beings it encounters. Something as simple as a change in rate of growth, such as we find in the salmon, can have a number of impacts on (for example) interspecies competition and resource deterioration.
The issue is simple: if we live in a world where things interact in complex ways, it is not ignorant or prehistoric or "New Age-y" to recognize that things interact in complex ways. However, if we insist that shooting genes randomly into a complex intertwined network is going to be ok, and that the potential effects can be self-monitored by biotech companies in short-term studies, then we are living in a bizarre, story-book version of the universe. It is fine to live in a simplified fantasy world if you are not doing any harm to those around you, but if you are actually modifying the evolutionary trajectory of the Earth's biosystems, then there is something to worry about.
Proposition 37 is the MINIMUM step we should take to improve this massive experiment. If genetically engineered products are labelled, we can more properly monitor health effects because we can easily establish (more or less) a control group (i.e. those refusing to eat it). To refuse to discriminate between both groups is to refuse to partake in properly establishing the scientific experiment. Those who are pro-science should feel confident in their decision to vote YES on Proposition 37. The deluge of scare tactic ads on California television, funded by big food corporations and biotech companies, does not make their arguments any more scientific. They are attempting to convince the public using power instead of evidence. To the extent that we succumb to their allure, we are still channeled by an instinct to be led by the powerful and authoritarian. This itself is probably the biggest hindrance of all to a scientific society valuing free inquiry.