His parenting time was restricted after a positive drug test. By federal standards, this would have been negative.

Kaitlin spent the first weeks of her newborn’s life in panic. The hospital where she gave birth in October 2022 had administered a routine drug test, and a nurse informed her that the lab had confirmed the presence of opiates. Child Protective Services opened an investigation.

A few months later, after searching her home and interviewing her eldest child and her ex-husband, the agency dropped its investigation, finding no evidence of abuse, neglect or drug use.

The amount of opiates that upended Kaitlin’s life — 18.4 nanograms of codeine per milliliter of urine, according to court documents — was so tiny as if she were a member of the Air Force pilot, she could have had 200 times more in her system and still been cleared to fly.

But for Kaitlin, the test sparked an investigation with potentially life-altering consequences. (ProPublica is using Kaitlin’s first name because her full name was redacted from court documents. She declined to be interviewed for this story.)

The ordeal “tempered what was otherwise supposed to be a joyous occasion” for the family, according to a trial filed in 2024 by the New Jersey Attorney General against the hospital system, Virtua Health.

The hospital said in a statement that it is “relentlessly committed to equitable, evidence-based care for every family.” In court documentshe denied the lawsuit’s allegation that he discriminated against pregnant patients and noted that Kaitlin had consented to the test. He also said New Jersey law requires him to submit reports on “substance-affected infants” to the state’s Division of Child Protection and Permanency. The trial is ongoing and a judge has referred him to mediation.

Drug testing labs typically report results in black and white: positive or negative. But a little-known fact about the industry is that these results are often based on completely discretionary standards. For example, almost all states use a threshold of 0.08% blood alcohol content to decide whether a motorist is intoxicated. But for other drugs detected in urine, saliva and hair, thresholds vary from test to test and lab to lab, including Kaitlin’s test for opiates.

There is no consensus among laboratories on the level that should confirm the presence of codeine in urine, said Larry Broussard, a toxicologist who wrote an academic journal article on “growing evidence” that poppy seeds in bagels and muffins cause positive test results. (Kaitlin ate a bagel shortly before taking her drug test, according to court documents.) There is more consensus for some other drugs, but labs still disagree on appropriate threshold levels for common drugs such as THC (the compound in marijuana that creates a high) and methamphetamine, Broussard said.

In 2022, the same year Kaitlin tested positive for codeine, the Department of Defense noticed an increase in personnel on military bases, attributing the positive tests to poppy seeds. Scientists at military laboratories concluded that a change in the manufacturing process of some poppy seeds led to contamination, leading the military to be falsely accused of drug abuse.

So far, 62 positive codeine tests have been “overturned and adjusted in Army records,” an Army spokesperson told ProPublica. In response, the Ministry of Defense doubled in March 2024 the military threshold for codeine tests to avoid false positives triggered by muffins, bagels and other poppy seed foods. Military personnel are now allowed to take duty with up to 400 times more codeine in their urine than is used to justify child welfare investigations in some states, ProPublica has found.

ProPublica examined threshold levels used to confirm the presence of common drugs, including opiates, methamphetamine, THC and cocaine, as cited in court records, lab contracts with government agencies and scientific journals, as well as in interviews with toxicologists. We found that the thresholds used by child protection systems vary significantly between jurisdictions. A major state agency, the Michigan Department of Health and Human Services, contractually required a laboratory to use levels it later admitted were “scientifically unsustainable.”

Ted Simon, an expert witness in toxicology and board member of the nonprofit Center for Truth in Science, which advocates objectivity in research, said agencies would be better off consulting with labs to set threshold levels. Indeed, “some laboratories carry out validation tests to guarantee the accuracy of their thresholds based on knowledge of human biology”. But even when labs set levels, they don’t always get them right. Some labs “simply use the sensitivity of chemical analysis to measure minute concentrations, with no way to assess suitability for humans,” Simon said. That can lead to situations like Kaitlin’s, where the hospital’s threshold was near the lower limit of what sophisticated laboratory instruments can detect, he said after reviewing her case.

Meanwhile, “labs tell their customers what they want to hear and are reluctant to disclose the uncertainty inherent in their methods,” Simon said.

There is no consensus in the industry on what should be done, or if at all, regarding different standards. Some experts say it is necessary to establish uniform levels, but acknowledge that it would require lengthy review before toxicologists and other stakeholders agree on what is appropriate. Others argue that as long as labs are transparent and back their decisions with research, they should continue to choose their own tiers. “Labs do what works with the instruments they have,” Simon said.

Child welfare agencies employ a patchwork of drug testing standards, according to contracts and procurement documents.

Some, like the Los Angeles County Department of Children and Family Services, require labs to use high thresholds that protect against false positives. Other agencies’ contracts with their drug testing services do not specify thresholds, leaving the decision up to the laboratory.

Some large agencies require labs to use ultra-low levels, which attract more users but carry risks. Accidental exposure to environmental substances and over-the-counter medications can trigger positive effects. “The lower the concentration you’re trying to detect, the more likely you are to get false positive results,” said toxicologist Paul Cary, who wrote a screening guide for drug courts, which aim to combat the addiction of people accused of drug crimes and avoid incarceration.

The federal government sets standards for drug testing of 14 million people. These include public sector employees as well as workers whose performance affects the safety of others, known as safety-sensitive roles, such as airline pilots, truck drivers and those who work at nuclear facilities. For decades, the program was known for its rigorous scientific review and inspection process to ensure accuracy.

In 2025, the second administration of President Donald Trump overhauled the Substance Abuse and Mental Health Services Administration, the federal agency responsible for the testing standards program, and laid off half of its staff. He also disbanded the expert group that had proposed scientifically valid threshold levels, the Drug Testing Advisory Council. “There could be national security concerns or security-sensitive issues that could be impacted given recent changes,” said Hyden Shen, former manager of regulatory and policy oversight at the health agency’s workplace programs division. In the spring, Shen resigned alongside nearly half his division. He spoke to ProPublica after leaving his federal job.

Private laboratories have long been free to set their own standards, independent of government recommended levels. federal ent. The CEO of a lab company that specializes in testing for probation departments, child welfare agencies and courts said in a lawsuit that in 2018 the lab lowered cocaine thresholds in hair follicle tests by a factor of five without changing its contract with the state child welfare agency. The company said the change was intended to align its levels with scientific updates and that state agencies were informed of the new thresholds when reporting test results. The lawsuit was settled, with the lab denying any wrongdoing.

Federal employees who test positive for drugs cannot be punished until their results are reviewed by medical examiners, doctors who verify that positive drug test results are not triggered by legitimate medications. (For example, without a special follow-up called an isomer test, the over-the-counter Vicks VapoInhaler is indistinguishable from illicit drugs in several types of drug tests.) But medical review of test results is expensive, and few state agencies require it for child welfare cases or to test people on probation. A laboratory vying for a contract to test probationers and juveniles at a Kansas residential facility has discouraged the use of medical examiners, saying it would “result in additional expense and additional time to obtain results.” Other state agencies, particularly those that oversee parole, probation or prisons, ignore confirmatory testing altogether and instead rely on cheaper, less accurate immunology tests unless someone challenges their result and can afford to pay out of pocket for follow-up, according to contracts between state courts and labs.

The agencies “are basically saying, ‘Most of these people have probably used drugs. And yes, OK, there are a handful who haven’t. But it would bankrupt us to have to confirm all of that,'” said Karen Murtagh, executive director of Prisoners’ Legal Services of New York, who has represented inmates in drug testing cases.

In the spring of 2019, Marie Herrera was working to reunite with her four children in Michigan’s foster care system. (ProPublica is referring to Herrera by her middle name at her request, to preserve her privacy as she moves forward in her life.) Hearing on her case, a foster care worker testified that everything was going well, according to a filing from her attorney: “The mother had attended all eleven parenting periods, had found employment, was in therapy, was living in three-quarters of the housing, and had tested negative for illegal drugs during the current reporting period.” »

Then in July of that year, Herrera’s saliva tested positive for cocaine. Herrera admitted to recovering from addiction, but denied using drugs. Over the next eight months, two more drug tests were confirmed positive for cocaine by the state laboratory. She requested testing from an outside laboratory, which did not detect illegal drug use.

According to his state lab test results, which Herrera shared with ProPublica, the levels of cocaine and its metabolite in his system ranged from 1.065 to 1.774 ng/ml, just above the state’s threshold of 1 ng/ml in saliva. If the positive test threshold for federal workers had been applied to Herrera’s tests, she could have had more than four times as much drug in her saliva and still been allowed to pilot a plane.

But Herrera’s positive test in December 2019 led the judge to take away unsupervised parenting time, according to court records.

“The positive drug tests turned my world upside down and ruined my life,” Herrera said. What she didn’t know was that, behind the scenes, Michigan’s child welfare agency was reviewing — and preparing to raise — its thresholds.

Levels of cocaine and other drugs in Michigan’s saliva were set by its drug testing provider, Forensic Fluids, in 2018, according to public records. (Forensic Fluids did not respond to a request for comment.) Michigan contractually required the same levels when it signed with a new lab, Averhealth, in 2019.

But the child welfare agency found conflicting results between its tests and those ordered by law enforcement, according to has public records. Some people who tested positive for a drug at one agency tested negative at another.

In November 2020, under the impetus of its new laboratory, the agency raised its levels. Communications between the agency and Averhealth show that both were concerned that low thresholds were not “medico-legally defensible” due to “uncertainty surrounding environmental exposure”.

“Current levels… are scientifically unsustainable,” Michigan’s child welfare agency wrote in a memo about the change.

In a statement, Averhealth, the lab that processed Herrera’s tests, said the inadequacy of results that concerned Michigan administrators “in no way calls into question the accuracy or reliability” of its tests. “Inconsistencies occurred when different types of tests were performed (saliva or hair) or when the individual was tested a few days later,” the company said, noting that “different types of tests have different limits.” The company said its test results “simply attest to whether a drug is present in a sample and, if so, in what quantity. It is up to the courts to decide the possible consequences.”

In Herrera’s case, the lab said, low cocaine positive levels “likely represent cocaine ingestion” and that “passive exposure as an explanation is highly doubtful.” The company also pointed out that Herrera tested positive for methamphetamine several times in the fall of 2020, nine months after the court took away his unsupervised parenting time.

Herrera admits that she has sometimes relapsed. But she also says that being labeled a cocaine user early in her case, when she said she didn’t use cocaine, derailed her recovery. Herrera believes this set her up for failure by creating an adversarial relationship with her social worker and her judge. “I wasn’t grateful for what they were doing to me,” she says.

Herrera’s parental rights ended in 2021, less than a year after Michigan raised its threshold levels for cocaine in saliva. In rejecting Herrera’s appeal, a judge cited, among other things, her refusal to participate in further drug testing, failure to take additional tests when she complied, and her lack of housing and income.

When Herrera was told she would never be able to see her children again, she was devastated and relapsed again. “Fuck, if they say I’m addicted, then I’ll numb the pain.”

“I think about my children every day,” she says. “It completely affected me.”

Even after raising its thresholds, Michigan’s levels remained well below those used for federal workers. The state declined to comment, but a memo said officials considered the federal levels inappropriate because they “do not assess the impacts on how these substances may affect a person’s behavior” or “how this use may impact the safety of children.”

Drug testing policy experts say it is not possible for any test, regardless of threshold, to reliably predict children’s safety.

“A drug test doesn’t tell you whether a person has a substance use disorder, whether they are in recovery, or whether a child is safe,” said Nancy K. Young, executive director of Children and Family Futures, which consults for child welfare agencies, and co-author of a Substance Abuse and Mental Health Services Administration policy document on drug testing for child welfare agencies. Young said administrators should view test results as “just one data point” and rely more on “casework and family relationships” to determine whether a child is safe and healthy.