A pilot study to assess lead exposure from routine consumption of coffee and tea from ceramic mugs: comparison to California Safe Harbor Levels

Abstract

Background: Lead (Pb) is a pervasive metal that can be found in, and potentially leached from, ceramics, particularly into acidic foods and beverages. The purpose of this study was to investigate potential lead exposure from coffee and tea consumption, given that both are acidic and routinely consumed from ceramic mugs. We measured the concentration of lead in coffee and tea at two different time points brewed in five readily available mugs known to contain lead. Results were compared to EPA's action level for drinking water and FDA's allowable level for bottled water. The measured concentrations, along with consumption patterns, were also used to calculate potential daily lead doses, which were compared to California's Safe Harbor Levels under Proposition 65. Additionally, we estimated changes in adult and fetal blood lead levels using EPA's Adult Lead Methodology model. Findings: The results of this pilot study suggest that lead in ceramic mugs can leach into coffee and tea. The measured lead concentrations ranged from 0.2 to 8.6 μg/L in coffee, and from <0.2 to 1.6 μg/L in tea. No statistical differences were found between the measured concentrations in coffee, tea, or water within each cup, or in the measured concentrations between retention times within each cup. However, a statistically significant difference was observed in the lead concentrations measured between cups, indicating that the lead concentrations were dependent on the cup used, rather than on the beverage or retention time. The estimated daily dose of lead exceeded the California Maximum Allowable Dose Level of 0.5 μg per day for one of the five mugs tested. Blood lead levels did not increase above regulatory or guidance values. Conclusions: This preliminary investigation provides data on potential lead exposures from daily beverage consumption among typical consumers, relevant to a substantial portion of the population, with particular implications for pregnant women.

Leaching of Potentially Toxic Metals (PTMs) from Two Nigerian Clays and Related Clay Pottery Used Locally as Foodwares

“…The order of concentrations, Fe>Mn>Zn>Pb>Ni>Cr>Cu>Cd for Kono-Boue Clay Pot is different compared to that of Ara-Ekiti Clay Pot, consistent with previous EDX elemental composition count data on Kono-Boue Clay by Gbarakoro [3]. The presence and elevated levels of the metals in clay deposits and enamels for ceramics have been highlighted in previous studies [10][11][12][13][14]. The presence of the potentially toxic metals, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn is also confirmed by the metal peaks indicated on XRF analysis results Ara-Ekiti (Figure 2) and Kono-Boue (Figure 3) clays.…”

“…The results from this study indicate that Cd, Cr, Cu and Pb were not in leachable forms in the Ara-Ekiti and Kono-Boue Clay Pots and the poor leachability of certain metals from foodwares has previously been reported by Anderson and Aderemi [13,14]. The non leachability of Cd, Cr, Cu, and Pb from the clays even at increased temperatures and pH conditions has previously been highlighted in adsorptions employing the Kono-Boue Clays for removal of Cr and Pb from water by Ajemba [15].…”

Assessment of the risk of exposure to cadmium and lead as a result of the consumption of coffee infusions

“…Those authors recount that up to 84% of Cd and up to 82.6% of Pb pass into the infusion, which is dependent on the coffee brewing method only (Turkish method—cooking—leaches more minerals, including toxic elements—except for Pb, than pouring with boiling water as practised in Poland), but it is not dependent on the type of coffee. Studies by Anderson et al [ 35 ] also showed that Pb can be leached from vessels into the ground coffee infusion—the highest amount of Pb passes from ceramic cups.…”

Migration of lead and cadmium from ceramic kitchenware and estimation of sampling uncertainty

“…The studies reported in the literature prevailed that extent of the migration depends on the properties of the food including oil and alcohol content and acidity level. In addition, the duration and temperature of the contact between the material and the food increased the migration (Ahmad et al, 2017;Anderson et al, 2017;Barnes et al, 2007;Belgaied, 2002;Chagas et al, 2020;Demont et al, 2012;Li, 2020a).…”