The pharmaceutical industry has a major role in global health via the development of medication, vaccines and treatments to enhance quality of life or prevent and cure dis-eases and medical conditions. The main contributions from this industry come in the form of research and development of drugs to meet the ever-changing healthcare demand.
This is a trillion dollar industry comprised of many subfields from discovery to market-ing. With technology and scientific advancements, the goal to produce newer or better medication with reduced side effects results in a very competitive and dynamic industry.
As our standards must evolve hand in hand with technological progression there is a need for better testing of developed drugs. Usually every new substance meant to be used on humans as a medical treatment, must undergo a series of pre-clinical tests, clinical trials and safety/compliance assessments to scrupulously meet every standard and regulation norm, before being launched into the market.
It is straightforward that the pharmaceutical industry is a very complex and diverse industry focused on tackling multiple global health problems. In this case study, we will be focusing on a specific global problem, nutrient deficiency, or, more specifically, iron deficiency. Iron is a very important nutrient for humans and animals alike because it is one of the few elements present in every cell on our bodies. Moreover, iron is present in many proteins that regulate most human body functions [41]. Some of the most notorious are: hemoglobin responsible for transporting oxygen to the tissues, cytochromes -enablers of electron transportation within cells, myoglobin - facilitators of oxygen storage in muscles, enzymes - regulation of internal cell reactions. These are just some examples, and there are several other body functions to which iron is directly connected such as
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neuronal and immune systems [42,43].
Iron deficiency is the most common form of nutritional anemia across the world, affecting more than two billion people according to WHO[44]. Moreover, it is also es-timated that about 50% of all anemia is due to iron deficiency. The symptoms of this kind of anemia are usually increased fatigue[45] and hindering of cognitive and motor functions which are even more impactful in development stages of the human body[46].
Therefore, this problem is increasingly problematic for pregnant women and may result in underweight babies or in more extreme cases in perinatal death[47]. The incidence of this problem is more impactful in developing countries due to the lack of means to diag-nose and treat iron deficiency anemia. Global perinatal, neonatal and maternal deaths numbers as reported by WHO have been systematically above several millions per year.
While it is hard to identify exact numbers of how many of these are related with nutri-tional anemia, it is known that it represents a big slice of the numbers. This could be completely preventable since the main form of treatment to this disease are iron supple-ments. WHO estimates that if iron supplements were easily accessible to everyone they would be enough to amend 42% of children’s anemia and 50% of women’s anemia[44].
In developed countries pharmaceutical iron supplements are a widespread response with multiple companies working on their development and distribution. The most common compounds used in this kind of supplements are based in ferrous salts like iron(II) or (III) sulfates and iron glycinate. Compounds based on iron sulfates are very easily accessible and therefore become very cheap and profitable to mass produce as a pharmaceutical drug. However, the ingestion of these kind of compounds has been connected with increased gastrointestinal tract and liver toxicity[48] as well as some other side effects.
The fact that some of the compounds might have hidden side effects would be enough to warrant further scientific analysis of these kind of samples. However, this research topic is further motivated by the fact that this type of drug is often just regarded as alimen-tary supplement and thus not as properly regulated or controlled as medical prescription drug. In fact, in many countries its acquisition and distribution is not really supervised whether the commercial transaction occurs on a pharmacy, drug store or even a general store. As a specific example, the supplements analyzed in this study are commercially distributed in Brazil where they are not regulated by their pharmaceutical regulatory body - ANVISA[49].
Furthermore, lower quality control can easily result in more contaminant substances in these supplements, usually of metal elements. These contaminants are unwanted ele-ments that can add unforeseen side effects to these drugs. Moreover, there has been some scientific evidence that in some cases, they might even degrade the active ingredient[50].
Two of the most common metallic contaminants found in these kind of supplements are manganese and nickel.
Manganese is both an essential and a toxic element, meaning that it can have its purpose in the human body nutrition but the body’s tolerance to it is not very high
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and, thus, can easily become toxic. On the nutrition side, the deficiency of this element can also lead to health problem because it functions as an activator and a constituent of several enzymes[51]. On the toxic side, manganese poisoning significantly impacts the respiratory tract and the brain, and may cause memory loss and nerve damage[52, 53]. The Scientific Committee on Occupational Exposure Limits suggest a limit based on lowest-observed-adverse-effect-level on animal studies for ingested manganese daily intake of 10-40µg per kg of body weight[54].
Nickel is slightly different from manganese in the sense that it is not documented to have beneficial effects to human health, it is only regarded as a toxic element. Keep in mind, that neither of these elements are as toxic as other substances like arsenic, mercury or lead for example. However, even though our tolerance to these elements is greater their toxicity still warrants caution. Nickel toxicity is correlated with lung cancer incidence, high blood pressure, neurological deficits, slower development in children[55]. Nickel has also been shown to have big correlation with the incidence of breast cancer[56,57].
Regardless of the known hazards of exceeding the dose of nickel intake there are appar-ently no set official daily maximum levels in food for consumption. The closest regulation, comes in the form of maximum concentration of nickel in water for human consumption, from the Council Directive 98/83/EC and the commission Directive 2003/40/EC, set to 20µg/L[58]. There is however, a relatively recent recommendation from the European Food Safety Authority of a maximum daily-ingested intake of nickel of about 2.8µg per kg of body weight[58].
Metal impurities are a very prominent problem associated with these kind of supple-ments that require a closer examination. Regarding pharmaceutical pills, in the USA, which agglomerate the biggest pharmaceutical industries, regulation of metal contami-nants has been historically done according the standard USP <231>[59]. This was done via chemical color test with a sulfide ion under a specific protocol and preparation con-ditions. This norm was substituted with the modern standards USP <232> (elemen-tal impurities limits)[60] and USP <233> (elemen(elemen-tal impurities procedures)[61], which are based on modern quantification techniques, which are much more accurate, such as inductively coupled plasma–mass spectrometry (ICP-MS)[62, 63, 64] or inductively coupled plasma–atomic (optical) emission spectroscopy (ICP-AES or ICP-OES)[65, 66].
Although ICP based techniques provide excellent limits of detection in the order of parts per billion, the sample preparation procedures often contains chemical treatment that negates the possibility of further analysis. Another issue with ICP-MS for the specific case of iron (54Fe and57Fe) is that for this technique there is a spectral interference with
14N40Ar16O38Ar and40Ar16O1H [62], which often warrants the use of pressured cell col-lision techniques. Thus, there has been increased research in providing alternatives to these standardized that provide other types of advantages. XRF is one of the most promi-nentcompetingtechniques whether under the form of WDXRF[67], standard EDXRF[68, 69,70] or even high-energy polarized-beam EDXRF[71]. As we have mentioned in chap-ter1XRF techniques provide a less expensive, portable, easier to use and non-destructive
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analysis, alternative do ICP.
In this study, we will be using EDXRF with triaxial geometry for fast and accurate multi-elemental analysis of iron supplements. The objectives are to determine with preci-sion how the measured iron content compares to the labeled one and to identify possible contaminants. In the end, this case study aims to prove adequacy of XRF technique as an alternative method to the standard ICP.