Men convicted of marijuana smuggling, bribery, armed robbery, burglary and theft have abandoned those endeavors in favor of a safer, richer business: Wholesaling pharmaceutical drugs in South Florida.

Lax state regulation and mild penalties have allowed at least eight convicted criminals to set up wholesale drug companies and obtain Florida permits to peddle the medicines Americans take daily.

The criminal element in the business has formed a network of companies trading hundreds of millions of dollars in medications, some of it phony, diluted, expired, relabeled or improperly handled, according to documents and state and federal officials investigating the industry.

These outfits also have built connections to supply other local wholesalers who sell to the nation's largest pharmaceutical distributors, turning South Florida into a major source of counterfeit and adulterated medications tainting the mainstream drug supply.

How lucrative can it be? Three wholesalers the state is investigating live in million-dollar homes in Weston's Windmill Ranch Estates neighborhood.

The state has licensed 422 Florida companies as drug wholesalers -- most of them tiny operations, from Miami to West Palm Beach -- plus 978 more who trade here from out of state.

The industry contends that small wholesalers play a legitimate role, holding down drug costs by snapping up overbuys and manufacturer specials at discounts, and reselling them to three huge nationwide firms that distribute about half of the country's drugs.

But investigators say the process has been subverted. Agents have traced deals in which unscrupulous wholesalers paid pennies on the dollar for bogus drugs or for bona fide medicines sold illegally by doctors, pharmacists and patients. The drugs were sold and resold among as many as 10 small wholesalers, each marking up the shipment to make a profit.

A special team of state and federal agents, for more than a year, has been investigating and presenting to a grand jury evidence of illicit trading in prescription drugs in South Florida.

Here are some of the wholesalers who are under investigation or have been arrested:

Michael Allyn Carlow

Carlow, 50, has emerged as a major wholesaler selling millions of dollars worth of questionable medications out of his $1.3 million home in Weston, investigators said in documents. He buys and sells using at least a dozen firms run by him or associates in seven states.

Carlow surfaced in the business in 1994, opening Quest Healthcare in Davie. Florida law forbids giving a wholesale license to a felon, but Carlow never mentioned that he had a felony conviction, and regulators never checked.

In June 2000, Carlow and an aide were arrested for buying 83 boxes of a costly, injectable cancer and AIDS drug, Neupogen, from witnesses working with investigators.

Carlow, his partner and the witnesses met on a Miami street corner. Carlow turned over $93,000 and loaded the medicine from the witnesses' trunk into his van. To remain potent, Neupogen is supposed to be refrigerated.

The state sentenced Carlow to 18 months probation and revoked his wholesale license. But he was able to stay in business, according to records.

Barely a month after his arrest, the girlfriend of his longtime associate started a wholesale firm under the name Med RX in Fort Lauderdale. On the day state inspectors visited Med RX, they found Carlow and his friend, Mark Novosel. Investigators say both help to operate the company.

Novosel had been arrested in 1980 as the planner and driver in a burglary that ended in the stabbing death of his elderly Ohio neighbor. His confession to his role was thrown out and the case was dropped, the prosecutor said. In 1998, Novosel was convicted of taking kickbacks and bribing a judge to send patients to substance abuse centers Novosel ran.

Another Carlow associate, David Ebanks, was arrested in Miami in April and found with fake driver licenses with his photos on them. The licenses were in the names of people who had agreed to set up wholesale firms on his behalf in Miami and Texas, allowing him to pose as them, state investigators said.