Scientists also found that infants can be exposed to "third-hand smoke" just from touching furniture and other objects in the home.
Georg Matt, a professor at San Diego State University, found that up to 90 per cent of the nicotine in the smoke adheres to nearby surfaces and early research suggests the chemicals can be swallowed, inhaled or absorbed through the skin.
The study of 49 babies under 13 months old found a nicotine byproduct cotinine in their urine and hair.
Meanwhile, Scottish researchers yesterday warned that children who suffer from a common gene defect could be at serious risk from passive smoking.
Scientists at Dundee University have discovered that young people with the defect - which is present in about 50 per cent of the population - are twice as likely to suffer from asthma and could also be at risk from developing potentially fatal lung diseases such as bronchitis and emphysema in the longer term.
Dr Somnath Mukhopadhyay said: "What I worry about is people smoking more and more in the home and you could potentially have a vulnerable population who are perhaps getting a higher dose of cigarette smoke."