either by gross or microscopic examination.
The two studies were done under essentially identical conditions, but tumors were seen only in
the first study. Statistically, it is unlikely that they were unrelated to the field and developed only in the
exposed group by chance. This suggests that an uncontrollable variable (UV) capable of inducing
tumors in conjunction with an EMF was present in the McElhaney study.
We too observed an EMF-related biological effect that was not seen in a replicate study; in our
case, however, it was possible to preselect the animals in the second study and thereby gain information
about the UV associated with the biological effect. In the initial study, we found secondary glaucoma in
10 of 60 rats that had been exposed for 30 days to 0.6-19.7 kv/m vertical electric fields; the glaucoma
was not seen in 43 rats exposed to horizontal fields (0.3 -9.7 kv/m) or in 72 controls (43). None of the
rats had been subjected to an ophthalmic examination prior to field exposure because the appearance of
eye diseases had not been anticipated. It was, therefore, not possible to determine whether the
glaucoma resulted from a worsening of an already existing defect, or was caused solely by the EMF.
These alternatives were examined in two vertical-field studies (2.8 kv/m, 19.7 kv/m) in which all
animals were subjected to a pretest eye examination with the bimicroscope and the indirect
ophthalmoscope. Rats that exhibited any identifiable disorder (iris hemorrhage, anterior synechia,
dacyroadenitis, keratitis) were destroyed, and only defect-free animals were placed on study. Following
30-day exposures, no cases of secondary glaucoma were seen in either the exposed or sham-exposed
rats 50 in each group). It seems to us, therefore, that our initial observations of secondary glaucoma
most likely stemmed from an exacerbation of preexisting eye defects by the EMF. The EMF, in any
event, could not have been the sole cause of the glaucoma.
The clearest example of the operation of a UV may be the multigeneration study done at the
Battelle Laboratories (54). Following the publication of our first multigeneration study (34), Battelle
was commissioned to replicate the work. The investigators first developed an exposure system that was
unexcelled with regard to field homogeneity and reproducibility of electrical environment. Every
aspect of the animals' physical environment-light, temperature, humidity, presence of pathogens in the
air, air flow, for example-was rigorously monitored and controlled by automatic equipment. The
investigators then constructed two complete exposure facilities: each consisted of a completely
characterized exposure unit, an identical unit for sham-irradiation, and a completely controlled
environment suitable for housing both units.
The multigeneration study was begun in the first exposure facility, and 3 weeks later a replicate
study was begun in the second facility; both replicates were done double blind. The body-weight data
for the males and females of each of the three generations in each replicate is shown in table 8.10.
Despite the fact that the maximum level of human intervention and control was exercised, and despite
the unprecedented resources devoted to the study, it was obviously not possible to eliminate the role of
a W: at the end the study, the males and females in the first replicate were statistically significantly
smaller than the controls, but in the second replicate they were significantly larger.
Table 8.10. AVERAGE BODY WEIGHTS IN THE BATTELLE MULTIGENERATION STUDY
ELECTROMAGNETISM & LIFE - 116