Evaluation of aluminium concentrations in samples of chocolate and beverages by electrothermal atomic absorption spectrometry

Abstract

Samples of chocolate, cocoa, tea infusions, soft drinks and fruit juice have been examined by, electrothermal atomic absorption spectrometry (ETA-AAS) for the presence of aluminium (Al). Fruit juices and chocolate were analysed after an adequate sample preparation; the other products were evaluated directly. Sampling was performed in duplicate for 248 independent samples. The mean Al concentration in chocolate was 9.2 +/- 7.5 mg kg(-1), and individual values were correlated with the per cent of cocoa in samples (Y = 0.63 + 0.27X, r = 0.78, p < 0.0001). Al concentration in commercial tea infusions ranged from 0.9 to 3.3 mg l(-1) (mean = 1.80 +/- 65 mg l(-1), whereas in laboratory-prepared samples it was 2.7 +/- 0.93 mg l(-1). In soft drinks, the concentrations of Al were lower, ranging from 9.1 to 179 microg l(-1); the highest values were observed in samples of orange squash (mean = 114 +/- 56 microg l(-1)). Apricot juice showed the highest Al level (mean = 602 +/- 190 microg l(-1)), being statistically, different from that of pear (mean = 259 +/- 102 microg l(-1)), but not different from that of peach juice (mean = 486 +/- 269 microg kg(-1)). Toxicologically, the amount of Al deriving from the consumption of these products is far below the acceptable daily intake of 1 mg kg(-1) body weight indicated by the FAO/WHO, and it is a verv low percentage of the normal Al dietary intake.

Determination of aluminum, copper and manganese content in chocolate samples by graphite furnace atomic absorption spectrometry using a microemulsion technique

“…The content of Al, Cu and Mn was directly correlated with the cocoa content. The Al values are higher than those found by Sepe et al (2001) (9.2 AE 7.5 mg/kg), but they agree with the values described by Jalbani et al (2007) From a toxicological perspective aluminum is a non-essential element to which humans are frequently exposed by ingestion of water and foods. Although the healthy human body has effective barriers to reduce systemic absorption of the ingested aluminum, exposure to this element has been implicated in a number of human pathologies including encephalopathy/dialysis dementia, Parkinson's disease and Alzheimer's disease.…”

“…Only a few literature reports have measured the metals content in chocolate (Sepe et al, 2001;Jalbani et al, 2007;Gü ldaş , 2008). The results obtained for the analyzed chocolate samples are reported in Table 5.…”

“…Methods from the literature for chocolate sample treatment involve microwave digestion, wet digestion and dry ashing (Sepe et al, 2001;Dahiya et al, 2005;Jalbani et al, 2007;Gü ldaş , 2008). Acids and peroxides are usually added to improve sample decomposition.…”

Trace elements in tea leaves, made tea and tea infusion: A review

“…In a defined diet study conducted in Australia to estimate oral Al absorption, instant tea provided 1.8 mg Al L − 1 , N50% of the 3.2 mg Al consumed daily (Stauber, Florence, Davies, Adams, & Buchanan, 1999). In general, tea infusions typically contain 2 to 4 mg Al L − 1 (Sepe, Costantini, Ciaralli, Ciprotti, & Giordano, 2001). However, Flaten and Odegard (1988) concluded from their review of the literature that concentrations of Al in brewed teas were commonly in the range of 2 to 6 mg L − 1 , whereas the levels of 40 to 100 mg Al L − 1 was reported by Coriat and Gillard (1986), which were typical and exceptionally in high amounts.…”

Rapid assessment of metal contamination in commercial fruit juices by inductively coupled mass spectrometry after a simple dilution

“…In addition the F AAS and AFS are mono-elemental techniques with lower linear range and usually higher detection limits. Accurate results without matrix effects and low LOD was obtained by Sepe et al (2001), using electrothermal atomic absorption spectrometry (ET AAS). However, this technique is mono-elemental and time consuming.…”