no doubt be directed largely toward meas uring the effects of radiation, but it mus t not be
overlooked that many chemicals are the part ners of radiation, producing precisely the same
effects. Some of the defects and malformations in tomorrow’s children, grimly anticipated by
the Office of Vital Statistics, will almost certainly be caused by these chemicals that permeate
our outer and inne r worl ds. It may well be that s ome of the findings about di minis hed
reproduction are also linked with interference with biological oxidation, and cons equent
depletion of the all-important storage batteries of ATP. The egg, even before fertilization, needs
to be generous ly s upplied with ATP, ready and waiting for the enormous effort, the vas t
expenditure of energy that will be required once the s perm has entered and fertilization has
occurred. Whe the r the s perm cell will reach and penetrate the egg depends upon its own
s upply of ATP, generate d in the mitochondria thickly clus tered in the neck of the cell. Once
fertilization is accomplis hed and cell division has begun, the s upply of energy in the form of ATP
will largely determine whe ther the developme nt of the embryo will proceed to completion.
Embryologists studying some of their mos t convenient s ubjects , the eggs of frogs and of s ea
urchins , have found that if the ATP conte nt is reduced below a certain critical level the egg
s imply s tops dividing and s oon dies.
It is not an impos s ible s tep from the embryology laboratory to the apple tree where a robin’s
nes t holds its complement of blue-green eggs; but the eggs lie cold, the fires of life that
flickered for a few days now extinguis hed. Or to the top of a tall Florida pine where a vas t pile
of twigs and s ticks in ordered dis order holds three large white eggs , cold and lifeles s. Why did
the robins and the eaglets not hatch? Did the eggs of the birds , like thos e of the laboratory
frogs , s top developing s imply becaus e they lacked enough of the common currency of ene rgy—
the ATP molecules—to complete their development? And was the lack of ATP brought about
becaus e in the body of the pare nt birds and in the eggs there were s tored enough ins ecticides
to s top the little turning wheels of oxidation on which the s upply of ene rgy depe nds? It is no
longer neces s ary to gues s about the s torage of ins ecticides in the eggs of birds , which obvious ly
lend themselves to this kind of observation more readily than the mammalian ovum. Large
re s idues of DDT and othe r hy drocarbons have been found wheneve r looked for in the eggs of
birds s ubjected to thes e chemicals , either experi mentally or in the wild. And the conce ntra tions
have been heavy. Pheasant eggs in a California experiment contained up to 349 parts per
million of DDT. In Michigan, eggs taken from the oviducts of robins dead of DDT pois oning
s howed concentrations up to 200 parts per million. Other eggs were taken from nes ts left
unatte nded as parent robins were s tricken with pois on; thes e too contained DDT. Chickens
pois oned by aldrin us ed on a neighboring farm have pas s ed on the che mical to thei r eggs ; hens
experime ntally fed DDT laid eggs containing as much as 65 parts per million.
Knowing that DDT and other (perhaps all) chlorinated hydrocarbons s top the energy-producing
cycle by inactivating a s pecific enzyme or uncoupling the ene rgy-producing mechanis m, it is
hard to s ee how any egg s o loaded with res idues could complete the complex proces s of
development: the infinite number of cell divisions, the elaboration of tissues and organs , the
s ynthes is of vital s ubs tances that in the end produce a living creature. All this requi res vas t
amounts of ene rgy—the little packets of ATP which the turning of the metabolic wheel alone
can produce. There is no reas on to s uppos e thes e dis as trous events are confined to birds. ATP
is the univers al currency of ene rgy, and the metabolic cycles that produce it turn to the s ame
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