That’s the claim of this book, which has made a thorough study of the after effects of radiation in food and the area surrounding Chernobyl, in addition to the continued distribution of food products from the Ukraine for a long time thereafter.
From an interesting interview on the book, explaining the difference, here’s an excerpt,
Karl Grossman: How did these people die? We are talking a million people dead from this nuclear plant accident. How?
Janette Sherman: They died of multiple different kinds of diseases from cancer, to heart disease, brain damage, thyroid cancer. But many, many children died in utero, in other words before they were born or died of birth defects after they were born.
Karl Grossman: How did these scientists determine 985,000 deaths as a result of Chernobyl?
Janette Sherman: Based on medical data that were available to the scientists.
Karl Grossman: Now what we’ve heard, frankly, since the accident, from the International Atomic Energy Agency (IAEA) — the global group which is supposed to regulate and promote nuclear power — currently on its website the IAEA says, the casualties of Chernobyl, maybe in all, 4,000 people are dead. That’s quite different from 985,000.
Another interesting thing to consider is that, following Chernobyl, and the fall of the Soviet Union, is that the Ukraine has faced the most massive population decline of any populous nation in the world, driven by infertility and low male life expectancy. The huge death rate, especially for a technologically advanced nation, is surely driven up by the high cancer deaths rate. To a lesser extent, Eastern Europe is effected in general, but not nearly to such a degree as the Ukraine (though Belarus and Bulgaria come close; and Russia is soon to follow), and this is the breadbasket of Europe, the nation with the third largest portion of arable land.
Perhaps the numbers are a bit exaggerated, but it should make you pause for a moment to consider the hugely destructive potential of a single nuclear disaster.
Traveling Dan 
