Poppy seed foods and opiate drug testing--where are we today?

Seeds of the opium poppy plant are legally sold and widely consumed as food. Due to contamination during harvesting, the seeds can contain morphine and other opiate alkaloids. The objective of this study is to review the toxicology of poppy seed foods regarding influence on opiate drug tests. Computer-assisted literature review resulted in 95 identified references. Normal poppy seed consumption is generally regarded as safe. During food processing, the morphine content is considerably reduced (up to 90%). The possibility of false-positive opiate drug tests after poppy food ingestion exists. There are no unambiguous markers available to differentiate poppy food ingestion from heroin or pharmaceutical morphine use. This is also a problem in heroin-assisted maintenance programs. A basic requirement in such substitution programs is the patients' abstinence from any other drugs, including additional illicit heroin. Also a lack of forensic ingestion trials was detected that consider all factors influencing the morphine content in biologic matrices after consumption. Most studies did not control for the losses during food processing, so that the initial morphine dosage was overestimated. The large reduction of the morphine content during past years raises questions about the validity of the "poppy seed defence." However, a threshold of food use that would not lead to positive drug tests with certainty is currently unavailable. Research is needed to prove if the morphine contents in today's foods still pose the possibility of influencing drug tests. Future trials should consider processing-related morphine losses.

Conversion of Cannabidiol (CBD) into Psychotropic Cannabinoids Including Tetrahydrocannabinol (THC): A Controversy in the Scientific Literature.

Cannabidiol (CBD) is a naturally occurring, non-psychotropic cannabinoid of the hemp plant Cannabis sativa L. and has been known to induce several physiological and pharmacological effects. While CBD is approved as a medicinal product subject to prescription, it is also widely sold over the counter (OTC) in the form of food supplements, cosmetics and electronic cigarette liquids. However, regulatory difficulties arise from its origin being a narcotic plant or its status as an unapproved novel food ingredient. Regarding the consumer safety of these OTC products, the question whether or not CBD might be degraded into psychotropic cannabinoids, most prominently tetrahydrocannabinol (THC), under in vivo conditions initiated an ongoing scientific debate. This feature review aims to summarize the current knowledge of CBD degradation processes, specifically the results of in vitro and in vivo studies. Additionally, the literature on psychotropic effects of cannabinoids was carefully studied with a focus on the degradants and metabolites of CBD, but data were found to be sparse. While the literature is contradictory, most studies suggest that CBD is not converted to psychotropic THC under in vivo conditions. Nevertheless, it is certain that CBD degrades to psychotropic products in acidic environments. Hence, the storage stability of commercial formulations requires more attention in the future.

Are adverse effects of cannabidiol (CBD) products caused by tetrahydrocannabinol (THC) contamination?

Cannabidiol (CBD)-containing products are widely marketed as over the counter products, mostly as food supplements. Adverse effects reported in anecdotal consumer reports or during clinical studies were first assumed to be due to acid-catalysed cyclization of CBD to psychotropic Δ 9tetrahydrocannabinol (Δ 9-THC) in the stomach after oral consumption. However, research of pure CBD solutions stored in simulated gastric juice or subjected to various storage conditions such as heat and light with specific liquid chromatographic/tandem mass spectrometric (LC/MS/MS) and ultra-high pressure liquid chromatographic/quadrupole time-of-flight mass spectrometric (UPLC-QTOF) analyses was unable to confirm THC formation. Another hypothesis for the adverse effects of CBD products may be residual Δ 9-THC concentrations in the products as contamination, because most of them are based on hemp extracts containing the full spectrum of cannabinoids besides CBD. Analyses of 362 hemp-based products of the German market (mostly CBD oils) confirmed this hypothesis: 39 products (11%) contained Δ 9-THC above the lowest observed adverse effect level (2.5 mg/day). Hence, it may be assumed that the adverse effects of some commercial CBD products are based on a low-dose effect of Δ 9-THC, with the safety of CBD itself currently being unclear with significant uncertainties regarding possible liver and reproductive toxicity. The safety, efficacy and purity of commercial CBD products is highly questionable, and all of the products in our sample collection showed various non-conformities to European food law such as unsafe Δ 9-THC levels, hemp extracts or CBD isolates as non-approved novel food ingredients, non-approved health claims, and deficits in mandatory food labelling requirements. In view of the growing market for such lifestyle products, the effectiveness of the instrument of food business operators' own responsibility for product safety and regulatory compliance must obviously be challenged, and a strong regulatory framework for hemp products needs to be devised.

HPLC analysis and safety assessment of coumarin in foods.

Coumarin is a component of natural flavourings including cassia, which is widely used in foods and pastries. The toxicity of coumarin has raised some concerns and food safety authorities have set a maximum limit of 2mg/kg for foods and beverages in general, and a maximum level of 10mg/l for alcoholic beverages. An efficient method for routine analysis of coumarin is liquid chromatography with diode array detection. The optimal sample preparation for foods containing cinnamon was investigated and found to be cold extraction of 15g sample with 50mL of methanol (80%, v/v) for 30min using magnetic stirring. In the foods under investigation, appreciable amounts of coumarin were found in bakery products and breakfast cereals (mean 9mg/kg) with the highest concentrations up to 88mg/kg in certain cookies flavoured with cinnamon. Other foods such as liqueurs, vodka, mulled wine, and milk products did not have coumarin concentrations above the maximum level. The safety assessment of coumarin containing foods, in the context of governmental food controls, is complicated as a toxicological basis for the maximum limits appears to be missing. The limits were derived at a time when a genotoxic mechanism was assumed. However, this has since been disproven in more recent studies. Our exposure data on coumarin in bakery products show that there is still a need for a continued regulation of coumarin in foods. A toxicological re-evaluation of coumarin with the aim to derive scientifically founded maximum limits should be conducted with priority.

Optimized LC/MS/MS analysis of morphine and codeine in poppy seed and evaluation of their fate during food processing as a basis for risk analysis.

The opiate alkaloids present in poppy seed intended for use in food recently have raised major concerns. An efficient method for routine analysis of morphine and codeine using liquid chromatography in combination with tandem mass spectrometry on a triple quadrupole instrument (LC/MS/MS) was therefore developed. The optimal sample preparation was found to be cold extraction of 10 g of unground poppy seed with 30 mL of methanol containing 0.1% acetic acid for 60 min shaken at 250 rpm. The fate of morphine during food processing was also studied. All experiments led to a significant reduction of morphine and codeine. For poppy cake only 16-50% of the morphine was recovered, and in poppy buns at the highest temperature (220 degrees C) only 3% of the original morphine content was found. Ground poppy seed showed significantly lower recoveries than untreated seed. Morphine elimination during food processing has to be taken into account in the current discussion about its maximum limits in poppy seed.

Benzene in infant carrot juice: further insight into formation mechanism and risk assessment including consumption data from the DONALD study.

Benzene was previously detected as a heat-induced contaminant in infant carrot juices. This study shows that carrot juice contains substances such as beta-carotene, phenylalanine or terpenes that may act as precursors for benzene formation during food processing. As benzene exposure has been associated with childhood leukaemia and other cancers, this study aimed to provide a quantitative risk assessment. To accomplish this, we used measured food consumption data from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study, along with survey data on benzene in different juice categories. The calculated exposures for infants between 3 and 12 months were low, with averages between 1 and 10 ng/kg bw/day, resulting in a margin of exposure above 100,000. The exposures were judged as unlikely to pose a health risk for infants. Nevertheless, carcinogenic contaminants should be reduced to levels as low as reasonably achievable. The focus should be set on improving the sterilization conditions.

NMR-spectroscopy for nontargeted screening and simultaneous quantification of health-relevant compounds in foods: the example of melamine.

The recent melamine crisis in China has pointed out a serious deficiency in current food control systems, namely, they specifically focus on selected known compounds. This targeted approach allowed the presence of melamine in milk products to be overlooked for a considerable time. To avoid such crises in the future, we propose that nontargeted screening methods need to be developed and applied. To this end, NMR has an extraordinary potential that just started to be recognized and exploited. Our research shows that, from the very same set of spectra, (1)H NMR at 400 MHz can distinguish between melamine-contaminated and melamine-free infant formulas and can provide quantitative information by integration of individual lines after identification. For contaminated Chinese infant formulas or candy, identical results were obtained when comparing NMR with SPE-LC/MS/MS. NMR was found to be suitable for routine nontargeted and targeted analyses of foods, and its use will significantly increase food safety.

Occurrence of benzene as a heat-induced contaminant of carrot juice for babies in a general survey of beverages.

A survey of benzene contamination of 451 beverage samples, using headspace sampling combined with gas chromatography and mass spectrometry (HS-GC/MS) with a quantification limit of 0.13 microg l(-1), was conducted. Artefactual benzene formation during headspace sampling was excluded by gentle heating at 50 degrees C only and adjustment of sample pH to 10. The incidence of benzene contamination in soft drinks, beverages for babies, alcopops and beer-mixed drinks was relatively low, with average concentrations below the EU drinking-water limit of 1 microg l(-1). Significantly higher concentrations were only found in carrot juice, with the highest levels in carrot juice specifically intended for infants. About 94% of 33 carrot juice for infants had detectable benzene levels, with an average concentration of 1.86 +/- 1.05 microg l(-1). Benzene contamination of beverages was significantly correlated to iron and copper concentrations, which act as catalyst in benzene formation. The formation of benzene in carrot juice was predominantly caused by a heat-induced mechanism, which explains the higher levels in infant carrot juices that are subject to higher heat-treatment to exclude microbiological contamination.