This is a hard one, but not an impossibility given what lies under the surface of seemingly "helpful" government efforts.  Take the Light Brown Apple Moth, for instance.  Here's a little creature that California's Terminator governor has taken a dislike to, and the LBAM eradication program is consequently underway in ... not farming but urban/suburban regions of the state of California.  An untested "pesticide" known as Checkmate (nice name!) will be sprayed aerially on citizens of California until 2010.  Why?  Because the Light Brown Apple Moth's mating habits must be "controlled," which moths number in the low thousands per population areas of 100,000 and more.  Checkmate will cost California taxpayers untold millions of dollars, as each aerial dose is $3.5 million (for, in one case, control of the mating of 750 moths).  Checkmate's effect on humans is ... severe reproductive-system problems particularly in women, along with the usual vomiting, intestinal distress, red urine and other inconveniences.  Checkmate is dropped in microcapsules composed of clusters of smaller capsules (3-4 microns) containing what the government calls "pheromones."  The point of the pheromones is to temper the moths' sexuality, but perhaps the contents are intended to act upon human reproduction, as they contain an endocrine disruptor which stimulates the body's production of estrogen (a female hormone; estrogen and progesterone govern the female reproductive cycle).  Most important, Checkmate is an untested "pesticide," enthusiastically approved for public use by Arnold Schwarzenegger, the California Department of Food & Agriculture and the EPA.  (Read Monterrey resident Rami Nagel's article on the LBAM here.)

(April '08 - The spraying has elicited strong reactions from Californians.  Watch YouTube video here.)

Some have reason to  believe that our exploding world population will be contained by deliberate covert strategies such as the one described above.  Bio-warfare is a research area we have all heard of, but we assume it to be intended for "foreign enemies" of the future.  Read this long article by geoscientist Leuren Moret and find out just how much civilian populations have been experimented on in drastic ways.  Watch a very informative Leuren Moret interview on depopulation here.  Also, a YouTube video of a San Francisco citizens' action meeting here, with remarks from Vietnam veteran General Bert Stubblebine on genocide.