Construction Sector Must Contend With Legal Marijuana in the Workforce


NAPLES, FL—Legal marijuana has become a major concern for construction employers with statistics showing it is contributing to more accidents, worsening the health of workers who use it, and it is responsible for lapses in their judgment and memory. With wider-spread use of marijuana in society, there are greater underlying risks to workers, company equipment and property, and public safety.

That was the message of Jeffrey Altholz, MD, C-MRO, of Clarity Testing Services, Inc. of Tarrytown, NY. He explored the subject in a presentation to some 175 contractors, suppliers and union officials at the Hudson Valley Construction Industry Partnership at the Ritz-Carlton, Naples, in late February. He told the group that the industry must put systems in place and take serious action to protect itself from these harmful effects.

In his address, “New York State Cannabis 2024 & Workplace Drug Testing,” he cautioned that, with laws and regulations changing almost weekly, companies that operate in states where marijuana is legal—either for strictly medicinal treatment or for recreational use as well—private enterprises have new responsibilities to keep up to date with evolving statues and provisions.

There are some 35 states now permitting medical marijuana, and 23 of them make pot available for recreational use, he explained. “The widespread legalization of marijuana has created safety concerns for employers and insurers in the construction sector, which already has some of the highest rates of workplace injuries in the country.” The drug remains illegal under federal law, and both forms are authorized in Washington D.C.

Dr. Altholz said studies have shown employees who tested positive for marijuana experienced 55% more mishaps and 85% more injuries than workers who tested negative. He added the respiratory problems occur more frequently in marijuana smokers, with a likelihood of greater workplace respirator usage. He cautioned that memory retention problems may lead workers to forget key safety procedures, and he noted that marijuana users are absent and tardy for work 75% more than non-users.

Impairment is defined as a state in which a person’s faculties are reduced so that his or her ability to see, hear, walk, talk and judge distances is below the normal level as defined by the state. Generally, impairment is caused by drug or alcohol use but can also be caused by mental or neurological illness, Dr. Altholz cautioned.

“Directing construction workers to climb up on a roof, scaffolding or to perform tasks where their motor skills may be impaired by the use of marijuana could go beyond problematic,” he theorized.

Employees in some safety-sensitive positions are still barred from using the drug even in states where it has been decriminalized for medical and recreational use, but for most companies in the construction sector, where finding qualified workers can be tough, the situation is exacerbated by the increased usage in these states. “There are several problems now converging. For example, drug-testing protocols that were designed years ago often fail to identify workers impaired by marijuana use,” Dr. Altholz said, adding that proven alternatives are often unavailable or unreliable.

While a growing percentage of states are decriminalizing the substance, it is still against federal law. “The conflicting legal environment has employers seeking ways to determine whether workers are under the influence of the drug in order to stave off workplace injuries and some of the costliest workers compensation claims,” one insurer noted.

Construction employers are familiar with alcohol impairment as a workplace hazard, but identifying marijuana intoxication can be more difficult, as the signs tend to be more subtle. And then there is growing pushback advocating for the rights of users. Some states are putting in place protections for workers who use recreational marijuana outside of work, placing constraints on employers. California, Connecticut, Montana, New Jersey, New York and Rhode Island have enacted workplace protections limiting employers’ ability to test for off-the-job marijuana use, according to the National Organization for the Reform of Marijuana Laws.

As Dr. Altholz forewarned, laws and regulations are changing weekly, placing new challenges on employers and other private enterprises to remain vigilant on the matter of workplace safety.

The state of New York legalized recreational marijuana only three years ago, but the rollout has drawn criticism from many for numerous delays and poor management. Other states have also moved to legalize cannabis, include New Mexico, Maryland and Missouri. Meanwhile, the U.S. House of Representatives passed a bill to decriminalize marijuana two years ago, but it stalled out in the Senate. The Bottom Line: Like alcohol, marijuana is now woven into the fabric of society, bringing new risks.

Oral Fluid vs. Urine Testing

Are there reliable tests at this point? As the industry prepares for the challenges ahead, saliva (oral fluid) is becoming the preferred way of testing—away from urine testing. “This is so important right now,” said Jeffrey Altholz, MD C-MRO, of Clarity Testing Services. “The recent approval by the U.S. Department of Transportation to rely on saliva testing is a game changer for the entire industry,” Dr. Altholz explained.

Although urine testing has been the tried-and-true drug testing method since the inception of the DOT testing requirements in the 1980’s, several changes have occurred making the decision of what type of testing to do uncertain. Over the last several years, key advances in oral fluid testing technology have now made saliva testing just as accurate than urine testing and provides several important advantages.

Urine testing is much less reliable than it used to be since 2012-14. That’s when production amped up for fake urine and products started hitting truck stops and gas stations to make available urine adulterants, including synthetic urine that is chemically indistinguishable from real urine. Demand for products with names like “Monkey Whizz” and “UPass” soared as nearly 1 million people were not working because of the epidemic of opioid use and drug addiction by 2015.

Oral Fluid Testing

Why is Oral Fluid so attractive?

Time: A specimen collection for saliva takes 3-5 minutes and is complete. No waiting for people to have to go to the bathroom or report shy bladders.

Observed: All saliva collections are observed avoiding the problems with fake urine.

Adulteration: Fake saliva has not yet been deployed/created as a way to subvert testing.

Panel: All panels are available including those with and without THC to comply with recent marijuana legalization guidance and DOL restrictions. SOURCE:

National Positive THC Drug Testing by Type

Testing to detect illicit substance use in the workplace reveals a disturbing increase of marijuana use since 2014 when Colorado legalized cannabis. Compared to oral fluid and hair testing, urine testing results (measured in green) is now much less reliable since 2012 when fake urine (chemically indistinguishable from real urine) became widely available.

Note: Despite the spike in positive test for THC since Colorado legalized cannabis in 2014, urine test positive rates have remained unchanged.

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