Consequences of criminalisation: the Dutch khat market before and after the ban

Exposure to DDT and HCH congeners and associated potential health risks through khat (Catha edulis) consumption among adults in South Wollo, Ethiopia

Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public health concern. In a market-based study, from five popular khat varieties, a total of 35 composite khat samples were analyzed for dichlorodiphenyltrichloroethane (DDT) and its main transformation products, and four hexachlorocyclohexane (HCH) isomers. Extraction was carried out by quick, easy, cheap, effective, rugged and safe method (QuEChERS). OCP concentrations were determined by head space solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS). Every sample contained β-HCH above the maximum residue limit set by the European Commission. For total DDT, this was the case for 25.7% of the samples. The ratios of (p,p'-DDD + p,p'-DDE) to p,p'-DDT were less than one for 85% of khat samples, demonstrating recent use of DDT in khat farmlands. Conversely, the ratio of β-HCH to total HCH varied from 0.56 to 0.96, implying historical input of technical HCH. Assuming a daily chewable portion of 100 g, dietary intakes of p,p'-DDT, total DDT and total HCH by adults ranged from 3.12 to 57.9, 6.49 to 80.2 and 39.2 to 51.9 ng (kg body weight)^-1 day^-1, respectively. These levels are below acceptable levels suggested by international organizations. Chewing khat showed lower non-cancer health risk, but showed relatively higher cancer risk in terms of OCPs. Because khat is chewed without being subjected to any treatment, uncertainties associated with estimated intakes and health risks should be low. Therefore, this practice is of great concern.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.

Impact of khat price increases on consumption behavior - price elasticity analysis

Background

The long border of Saudi Arabia with Yemen is the primary route for khat entry to the Kingdom. As of April 2015, the government of SA tightened the border, making it more difficult to import khat into the country. As a result, local user prices of khat probably increased due in part to higher supply costs and perhaps lower quantities. One anti-drug strategy is to increase consumption cost by increasing the price of supply. We aim in this study to measure the responsiveness of khat demand to price changes.

Methods

This study used a cross-sectional survey design. Two stage sampling was used to recruit 350 khat chewers from four selected primary healthcare centers in Jazan province (South western province of Saudi Arabia). The data were collected during the first quarter of 2017. This study used both contingent valuation and revealed preference methods to assess the impact of price increases on the purchasing of khat. Graphical analysis, paired-samples t-test, and one-way repeated measures analysis of variance (ANOVA) were used to assess the impact of price increases on khat consumption.

Results

The study results showed a significant decrease in khat consumption amount (t = 8.63, p ≤ 0.05), frequency (t = 30.42, p ≤ 0.05), and expenditure (t = 34.67, p ≤ 0.05) after the tightening of the Saudi–Yemeni border. Hence khat demand is price elastic. The price elasticity of khat demand in Jazan is estimated to be between − 2.38 and − 1.07. Therefore, each 1% increase in price is associated with 1–2% reduction in quantity demanded. This means khat chewers are relatively responsive to price changes (i.e., khat demand is price elastic). Repeated measures analysis of variance showed price increases significantly affect the quantity {F(4, 2.58) = 257, p ≤ 0.05, ηp² = 0.423} and frequency {F(4, 1.83) = 415, p ≤ 0.05, ηp² = 0.543} of khat chewing.

Conclusions

Increased prices for khat would significantly decrease demand. Accordingly, we recommend implementing law enforcement strategies focused on disrupting the khat supply chain to realize high prices and so discourage use, hence reducing the incidence of khat-related illnesses.