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Human data support the finding that effects of lime are limited to the external surfaces of the body (local irritation) and no systemic effects are anticipated. If inhaled, the critical effects of hydraulic lime dust can be expected to be sensory irritation and a decrease of lung function parameters at long-term exposure, by read-across from CaO and Ca(OH)2.

Calcium supplementation during pregnancy is not adverse, but instead may be beneficial both to the mother and to the offspring.

Calcium appears to reduce the risk of recurrent colorectal adenomas

Toxicokinetics of calcium has been investigated in a range of human studies, which are summarised in section 7.1.1 of the technical dossier.

Case reports underline the irritating properties (skin and eye) of Ca(OH)2, being the main constituent of lime (chemical) hydraulic.

Additional information

Studies summarised in section 7.10.1 report individual cases or epidemiological data regarding human exposure to lime (or cement as surrogate for the alkaline effects of lime). Cain (2004), Torén (1996), Lahaye (1987), Wegman (1991), Vestbo (1991), Fell (2003), Yang (1996), and Eid (1969) form the basis of the SCOEL recommendation of occupational exposure limits (inhalation). Cain (2008) is provided as a supplementary reference to Cain (2004), confirming the nature of effects upon short-term exposure to CaO, which are described as sensory irritation and slightly increased secretion from the nasal mucosa. Meo (2003), and Al-Neaimi (2001) are provided as additional references describing typical symptoms of long-term over-exposure to cement dust, typically being reduced pulmonary function, pleural thickening and chronic bronchitis. Since the primary effect of both CaO/Ca(OH)2 and hydraulic lime upon inhalation are anticipated to be equivalent (local irritation due to pH shift), the above studies are used in support of hydraulic lime by read-across.

Villar (1990), Levine (1997), Koo (1999) are used as supportive data for the endpoint "developmental toxicity/teratogenicity" (section 7.8.2), demonstrating either a beneficial effect of lack of adverse effects of calcium in pregnancy, both to mothers and their offspring.

Belizán (1991) reports a protective effect of calcium against hypertensive disorders in pregnant women.

Baron (1999) reports that calcium supplementation is associated with a significant - though moderate - reduction of the risk of recurrent colorectal adenomas.

The references Johnston (1992), Lloyd (1993), Elders (1994), Reid (1993), Moser-Veillon (2001), Rosado (2005), Wastney (2000), Braun (2008), Minihane (1998), Sokoll (1992), Kalkwarf (1998), Peacock (2000), Dawson-Hughes (2002), and Bonjour (1997) are dealing with toxicokinetic parameters of calcium and are therefore reflected in section 7.1.1, together with SCF and FAO/WHO documents in a weight-of-evidence approach.

No relevant classical epidemiological data (section 7.10.2) have been identified.

Studies summarised in section 7.10.3 provide examples of human cases of eye irritation due to accidental exposure to calcium hydroxide (Schmidt, 2008), and skin corrosion due inadvertent exposure to wet cement over several hours (Rados, 2005). In the latter case, it is important to note that aqueous cement slurry has been found to result in substantially higher pH values (>13.5) than CaO or Ca(OH)2 alone. Therefore, the corrosive phenomena reported this case study should not be extrapolated to lime. Overall, the two human case studies summarised in this section demonstrate that exposure to hydrated lime or mixtures based upon lime may result in eye or skin irritation, particularly upon prolonged skin contact.

No sensitisation data in humans were retrieved (section 7.10.4).

Relevant exposure-related observation (section 7.10.5) other than those addressed in section 7.10.1 and 7.10.3 were not identified.