Assessment of the combined nitrate and nitrite exposure from food and drinking water: application of uncertainty around the nitrate to nitrite conversion factor

Abstract

Dietary exposure to nitrate and nitrite occurs via three main sources; occurrence in (vegetable) foods, food additives in certain processed foods and contaminants in drinking water. While nitrate can be converted to nitrite in the human body, their risk assessment is usually based on single substance exposure in different regulatory frameworks. Here, we assessed the longterm combined exposure to nitrate and nitrite from food and drinking water. Dutch monitoring data (2012)(2013)(2014)(2015)(2016)(2017)(2018) and EFSA data from 2017 were used for concentration data. These were combined with data from the Dutch food consumption survey (2012)(2013)(2014)(2015)(2016) to assess exposure. A conversion factor (median 0.023; range 0.008-0.07) was used to express the nitrate exposure in nitrite equivalents which was added to the nitrite exposure. The uncertainty around the conversion factor was taken into account by using conversion factors randomly sampled from the abovementioned range. The combined dietary exposure was calculated for the Dutch population (1-79 years) with different exposure scenarios to address regional differences in nitrate and nitrite concentrations in drinking water. All scenarios resulted in a combined exposure above the acceptable daily intake for nitrite ion (70 µg/kg bw), with the mean exposure varying between 95-114 µg nitrite/kg bw/day in the different scenarios. Of all ages, the combined exposure was highest in children aged 1 year with an average of 250 µg nitrite/kg bw/day. Vegetables contributed most to the combined exposure in food in all scenarios, varying from 34%-41%. Food additive use contributed 8%-9% to the exposure and drinking water contributed 3%-19%.Our study is the first to perform a combined dietary exposure assessment of nitrate and nitrite while accounting for the uncertain conversion factor. Such a combined exposure assessment overarching different regulatory frameworks and using different scenarios for drinking water is a better instrument for protecting human health than single substance exposure.

Reviewing chemical and biological risks in urban agriculture: A comprehensive framework for a food safety assessment of city region food systems

“…As a result, leafy vegetables from any cultivation typology may contain nitrate concentrations higher than those recommended by the European Commission in 2011 (600–2000 mg kg −1 of product, EU Commission Regulation No 1258/2011). For the sake of clarity, it should be considered that nitrate intake includes multiple dietary and non-dietary sources other than vegetables, such as food additives, processed meat ( Honikel, 2008 ) and drinking water ( van den Brand et al, 2020 ).…”

Effect on health from consumption of meat and meat products

“…In addition, nitrates ingested through meals have important significance as a fundamental component of NO, and it has been reported that foliage such as cabbage and root vegetables such as radish contain a large amount of nitrates. van den Brand et al [ 61 ] studied the dietary exposure assessment of nitrate and nitrite from all sources and reported that the vegetables contributed the most to the combined exposure in food in all scenarios, varying from 34%–41%. Food additive use contributed 8%–9% to the exposure, and drinking water contributed 3%–19%.…”

Estimativa do consumo de nitrato e nitrito por escolares da rede pública: um estudo longitudinal

“…Estudos, que serão descritos na sequência, apontam que a presença destas substâncias em alguns alimentos e na água promovem efeitos deletérios à saúde humana, uma vez que são precursores de compostos nitrogenados (N-nitrosos) com atividade carcinogênica, como as nitrosaminas e nitrosamidas, sendo que a exposição dos indivíduos a estes compostos deve ser limitada aos menores níveis possíveis (SCHUDDEBOOM, 1993). VAN DEN BRAND et al, 2020;XIE et al, 2016). A estas substâncias são associados os efeitos carcinogênicos atribuídos às carnes processadas.…”

“…É sabido ainda que, cerca de 45% a 75% da exposição dos indivíduos aos compostos N-nitrosos é originada deste processo endógeno (TRICKER, 1997). Esses alimentos de origem animal podem, ainda, ser fontes de compostos n-nitrosos formados exogenamente, ou seja, durante o próprio processamento do produto, como na cura das carnes e no aquecimento dos produtos cárneos em temperaturas elevadas (CROSS et al, 2010; VAN DEN BRAND et al, 2020). Além disso, o ferro presente, principalmente, nas carnes vermelhas favorece a formação de nitrosaminas e nitrosamidas no organismo humano (CATSBURG et al, 2014;LUNN et al, 2007).…”

“…Estes resultados variaram de 1,05 mg de nitrato/kg de peso/dia a 9,4 mg de nitrato/kg de peso/dia. Assim, a EFSA concluiu que os valores para ingestão diária aceitável de nitrato precisam ser reavaliados (EUROPEAN FOOD SAFETY AUTHORITY, 2017a; 2017b; VAN DEN BRAND et al, 2020). Vale ressaltar que, de acordo com Schuddeboom (1993), a dose oral letal para o nitrito estaria entre 33-250 mg/kg de peso corporal, e para nitrato, 80-800 mg/kg de peso corporal.…”