Addiction is now America's number one health hazard, reports a recently released New York state study, exceeding cancer, respiratory illness and even heart disease in deaths, disabilities and total costs to the nation. Alcoholism is one of the most widespread of these addictions.

Of every 10 people who drink, estimates the National Council on Alcoholism, one is an alcoholic. For every alcoholic, three to four other people's lives are seriously disrupted by the drinker's illness. Two journalists who crossed the thin line from social drinking into addiction--and then fought their way back to sobriety--have written books about their experiences. They discussed those experiences in recent interviews. Paul Molloy: Pride Was The Biggest Obstacle

In 1961, nationally syndicated columnist Paul Molloy wrote a joyful account of life in his large family entitled And Then There Were Eight. Twenty years, a divorce and several alcoholic breakdowns later, he says, "now there's just one--me." Although the 62-year-old journalist had been drinking since age 19, and would periodically go on week-long liquor binges, he first began to suspect he had a problem the night he walked into the wrong house in his Chicago neighborhood and "nearly scared a sleeping couple out of their wits."

That episode had capped a typically spirited day in the life of the Chicago Sun-Times television columnist: "a 10 a.m. interview with an actress who liked bloody marys, a multi-martini lunch with the news director of a television station, a 4 p.m. cocktail party, a 5 p.m. interview-on-the-rocks with the producer of a new television series, and finally, a dinner show staged by the Chicago Emmy Awards people.

"I liked to get a little warm glow before meeting interesting people in that so-called glamorous world. I never mixed drinking and writing, and I never missed a column. But occasionally I would write two or three in advance so I could safely take a few days off."

Despite occasional memory lapses and embarrassing incidents, Molloy refused to admit he was alcoholic until his wife of 32 years divorced him in 1975. He quit his job--"I had said all I had to say"--and spent several years moving from apartment to apartment--"reading, writing, drinking and playing Scrabble.

"Through it all . . . ran the wrenching pain of loneliness. I would bang cupboard doors to break the intolerable silence and stomp away from the typewriter, moaning, 'Where did everybody go?' "

Finally, after a two-day vodka binge, Molloy checked into the Alcoholism Rehabilitation Service at the Hinsdale Sanitarium in suburban Chicago. Through that experience, and the intervention of a psychiatrist friend, he stopped drinking.

Since "alcoholics stay sober by helping others stay sober," Molloy has written the saga of the disasterous effects his alcoholism had on his family and himself in Where Did Everybody Go: Portrait of an Alcoholic (Warner, 237 pages, $2.95).

"It was only after my marriage came apart and I was living alone," he writes, "that I realized I was not the only one at home with a drinking problem. All of my eight children had one, too. And so did my estranged wife . . . because the people around an alcoholic are vulnerable.

"Children, especially, sense that something is wrong, but since they do not fully understand what is going on--that the alcoholic father is projecting his own lack of self-esteem--they frequently feel as much guilt as he does."

He describes in heart-breaking detail, his eight children's memories of his alcoholism. When his daughter Georgia was 10, she would steal his bottles and empty them into the kitchen sink. Paul Jr. remembers his father "slipping away for an inning or two" at Little League games and being "too embarrassed to bring my friends home." Another daughter, Nelda, recalled feeling "like we were all in a battle together, and we got scars."

And every birthday, his daughter Marcia's wish was "that Daddy would stop drinking. I never gave up hope because he was always trying . . . The deviant part is that we manipulated him when he drank; like we could get the car, and money or stay out late. But we didn't like what we were doing."

The biggest obstacle in Molloy's journey to sobriety, he says, "was my pride. I was too bright, too successful to be an alcoholic. I had considered alcoholism a moral fault. I'd always wished I could pinpoint some reason why I drank. But I'd had a wonderful childhood, a great job, a terrific family. So why was I doing this to myself?"

After years of treatment, he says, "I finally accepted the concept of alcoholism as an illness. If the American Medical Association, the World Health Organization and numerous others say it's a disease, I decided I would, too. I think there's something in my emotional and chemical make-up, a blend of the psychological and the physiological that made me susceptible to the illness."

The key elements that separate a social drinker from an alcoholic, Molloy says, are "dependence and preoccupation." The worst thing a family member can tell an alcoholic, he says, "is 'If you loved me you'd stop drinking.' That's nonsense. It's not a matter of willpower. The alcoholic has to want to stop. Encourage treatment . . . get help from Alcoholics Anonymous.

"Sobriety is a change of attitude, a new way of thinking and of life. You have to learn to like yourself and be happy with yourself. If you're not, you'll do the easiest thing--drink." Robert McCormick: 'Booze Everywhere'

For Robert McCormick, a typical day as NBC-TV's Senate news correspondent started and ended with a drink. First came the eye opener. Throughout the day on Capitol Hill, he says, "there was booze everywhere." Back in the newsroom he kept a bottle in his desk. After the news report came the nightcap.

"I drank most all of the time," admits McCormick, 70, who entered an alcoholic rehabilitation center shortly after retiring in 1976. "I tried not to go on the air when I was too drunk. But I think a lot more people on the air were potted a lot more than we realize."

A Washington native, McCormick bought his first booze at age 14--during Prohibition--from an ice cream parlor that bootlegged whiskey. As a young reporter with the former Daily News, he drove a Model-A roadster to the Maryland mountains with his editor, the legendary Ernie Pyle, to buy moonshine.

Toward the end of his nearly half-century journalism career, "I drank better than a quart a day." Although he imbibed "anything I could get my hands on . . . like most alcoholics I preferred vodka. It's fairly tasteless, you get the jolt fast and you have the residual idea that it doesn't smell on your breath--which it does."

If his drinking affected his work, says McCormick, "no one said anything to me about it. A lot of them were doing the same thing." His wife, however, urged him "for years" to seek help, which he did upon retiring from NBC. But when his wife died, three weeks after he was discharged from the alcoholic rehabilitation center, he plunged back to the bottle.

Over the next year he "served time" in three more "drunk tanks . . . as we veteran sober alcoholics sometimes refer to them." On his final stay, five years ago, "I felt a change in my physical being. Over the course of a few days, I lost whatever it was within me that craved alcohol. I have no idea why. There was no particular incident that caused it. But I think there was a change in my body chemistry. We know chemical imbalances can result in schizophrenia and manic depression. So why not alcoholism?"

When word got around that "Bob McCormick was again relatively normal," he says, "the telephone calls started. They were mostly pleas for help. Some came directly from alcoholics themselves, the rest from frantic relatives and colleagues of alcoholics. They hadn't the faintest idea where to turn."

As a result of this "amazing amount of ignorance about alcoholism," McCormick wrote Facing Alcoholism (Oak Tree Publications, 231 pages, $12.95). "It's not a memoir," he asserts quickly. "I always detested people who write memoirs. It's simply an effort to tell people how to meet the problem of alcoholism in a pragmatic way."

People confronted with alcoholism most often think of four avenues of assistance, McCormick says, "a physician, a psychiatrist, a clergyman and Alcoholics Anonymous. The first three are too often a waste of time; the fourth is potentially great but frequently entails overwhelming difficulties.

"Most family doctors know little about alcoholism . . . many psychiatrists wisely will not even attempt to treat alcoholics . . . clergymen try reason based on religion and conscience that seldom penetrates the mind befuddled by excessive use of the most easily obtainable narcotic in the world. AA is one of the greatest organizations in the world . . . but a sizable portion of people who need or want help are turned off by it."

The "fifth hope," says McCormick, is the alcoholic rehabilitation center. With a cure rate of about 60 to 80 percent at the best clinics, he notes, "they are far from infallible. Yet the clinic affords the most concentrated, presumably the most skillful treatment now known. And it can be the first resort, rather than the last."

The biggest myth about alcoholism, he says, "is that it's just a matter of willpower or bad moral character. A lot of that stigma still exists."

But like cancer or the common cold, he notes, "alcoholism is a disease." Alcoholics differ from heavy drinkers, "because they are addicts who must have the alcohol to perform. The heavy drinker doesn't necessarily have to have a drink to function."

McCormick advises family members of problem drinkers to "start a concentrated campaign to get the person to treatment. It requires a lot of maneuvering to reach a drunk. Keep trying different approaches until you get a response." Two common mistakes relatives make are hiding the booze--"they can always get it somewhere"--and publicly humiliating someone who drinks too much--"that just intensifies the drinking."

Today McCormick considers himself a "stabilized" alcoholic. "I keep booze in the house and serve it, but I have no craving to drink myself. I'm not about to try. It's not worth it."