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Recently, the problem relevant to the increasing presence in the environment of platinum group metals (PGMs) have been a topical subject of great interest, even if the scientific attention has been generally addressed to platinum(II), palladium(II) and rhodium(III), and in few cases to iridium(III), osmium(VIII) and ruthenium(III). This is because the PGMs concentration is significantly growing as a consequence of their increasing use in the production of industrial catalysts, anticancer drugs, jewels, and especially autocatalytic converters. In the case of the last tools, their continuous incorrect use “stop and go” with consequent deterioration implies a considerable release of these metals in the environment. Even if initially the metals used in autocatalytic converters were platinum, palladium and rhodium, in recent years such PGMs were gradually replaced in part, or alloyed with osmium, ruthenium and, especially, iridium. In particular, in the last decade, and always more frequently, iridium is employed as alloying (10-20 % w/w) with platinum, palladium and rhodium in the manufacture of autocatalytic converters in order to withstand high temperature and high wear. Finally, it is also important to highlight that iridium is one of the least abundant elements in the environment, and, probably for this reason, very few data are available. Thus, this work intends to propose voltammetric methods for the determination of ultra-trace iridium in environmental samples: airborne particulate matter, superficial waters, soils/sediments, vegetables, mussels, clams and algae. To better validate the proposed analytical procedures, a critical comparison with spectroscopic measurements — electro-thermal atomic absorption spectroscopy (ET–AAS) because of its well established and tested robustness — has been also carried out and discussed here, taking into account all the parameters of interest to set-up an analytical method, such as precision, trueness, limit of detection and quantification, selectivity and, especially, sensitivity.

The widespread use has made preservatives become a special monitored group in commercial cosmetics, especially in the leave-on products due to the prolonged exposure. Additionally, recently there has been an increase in the demand for preservative-free cosmetics related to undesired adverse effects on human health, in order to minimize the amount in personal care products or produce preservative-free-cosmetics and verify the contents to avoid health risk. Hence, the simultaneous separation and trace-level determination in personal care products are important for both merchandise reliability and quality assurance. However, is not possible to exclude that heavy metals can be accumulated in the body over time and repetitive metal-containing product application can lead to significant exposure levels. In the case of some metallic powders such as nickel (Ni), lead (Pb), and cadmium (Cd), they are unintentionally added to the cosmetics as impurities during manufacturing of an ingredient or product, and represent a minor source of exposure compared to other pathways such as water, food or air. For these reasons it is necessary a deep knowledge of real toxics (organic and inorganic) content into personal care products and cosmetics using reliable, high-throughput, sensitive and selective analytical assays. In this chapter, recently developed method for the extraction, separation, and quantitative determination of organic (phthalates and parabens) and inorganic toxic (heavy metals) in cosmetic products are reported.

Cosmetics are widely used even for daily usage. Raw materials and industrial machines used for their preparation are inevitably affected by contamination from metals, because these species are ubiquitous in the world. For instance, nickel, lead and cadmium are frequently unintentionally added to cosmetics as impurities during manufacturing. In fact, some metals are very dangerous for human health. This is true over safe limits of concentration even in the case of metals which are essential for human metabolism. Moreover, heavy metals may accumulate in the body over time and repetitive product applications, leading to significant exposure levels. International regulation about metals in cosmetics is very heterogeneous from Country to Country. Moreover, in many Countries the regulation is incomplete or absent. In some cases, regulations provide safe limits, but the analytical techniques useful to check for those limits are not indicated. In other cases, the safe limits are below the limit of detection of available analytical methodologies, hence the development of new methods is necessary. For these reasons, a deep knowledge of metals content in personal care products and cosmetics is necessary using reliable, and high-throughput, sensitive and selective analytical assays are needed. The present review proposes an exhaustive focus onwhat arethemetalsof interest, and what is the state of the art about analytical methodologies suitable to detectthesetoxic metals in cosmetics and personal care products (PCPs). This review would also be a stimulus to solicit International Organizations to fill the gap of the lack of strict and comprehensive laws regulating the maximum allowable concentrations for an increasing number of contaminants in these matrices, especially considering their enormous daily use.

Recently, pollution linked to airborne particulate matter has drawn attention. The issue is due to a drastic increase of anthropic activities: industrial activities, in all their different typologies, and more and more increasing vehicular traffic. As a consequence, the totality of the pollutants associated with the various types of particulate are everywhere strictly dependent on the type of source of the same particulate. Moreover, the particle size evidently has a particular importance, since the decrease of the aerodynamic diameter of particulate corresponds to greater ease of penetration of the same particulate in the deeper levels of the respiratory system. This obviously is a serious problem for human and animal health, implying high costs in health care. Due to multiple simultaneous sources in areas at high anthropic impact, there are many pollutants associated with airborne particulate matter, both of inorganic and organic kind, and even simultaneously present on the same particulate samples. In any case, the pollutant determination in airborne particulate matter certainly must be accurate, reproducible and it must be especially characterized by very low limits of detection. In particular, the present work reports and discusses the different analytical procedures for the voltammetric and spectroscopic determination of heavy metals and metalloids (copper, lead, cadmium, zinc, mercury, tellurium, arsenic, selenium, tin, antimony, vanadium, nickel, chromium) in airborne particulate matter sampled in two sites, differently influenced by anthropic pollution. An additional sampling, carried out in a zone at very low anthropic impact, was chosen for eventual comparisons. The chosen particulate-matter size was PM2.5 (aerodynamic diameter < 2.5 µm) even if the proposed methodologies evidently can be also applied to all other particle sizes of interest. A separate section will be dedicated to the analytical procedure for the determination in airborne particulate matter of new emerging anthropic polluting traffic-related pollutants, i.e. the platinum group metals (PGMs) — platinum, palladium, rhodium, osmium, ruthenium and iridium — that, in the last decade, have aroused much interest from scientific community.

The work regards the voltammetric determination of trace metals in different kinds of food matrices. First goal is relevant to the correct analytical procedure for the voltammetric determination of trace and ultra-trace metals - Platinum Group Metals (PGMs), Mercury (II), Copper (II), Lead (II), Cadmium (II) and Zinc (II) - in meals, vegetables, mussels, clams and fishes: this allows, evidently, to check high quality foodstuffs. The second goal is to show the advantages that the electrochemical approach may offer over atomic absorption spectroscopy. First, voltammetry, together with the standard addition method, is a valid analytical technique (good selectivity and, especially sensitivity) for the simultaneous element determination in complex matrices and it does not require enrichment steps, like solvent extraction, and/or particular sample treatments. Second, as regards precision, accuracy and limits of detection, the results obtained with the two techniques are both good and comparable in all cases, although voltammetry is better than atomic absorption spectroscopy, allowing simultaneous metal determinations in most cases. In fact, also Inductively Coupled Plasma (ICP) and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) permit multi-element determination, but the great advantage in using voltammetry is certainly the equipment-related costs: very low in the case of voltammetry, extremely high in the case of ICP and ICP-MS, in the latter case as much as 25-30 times higher. In this work Electrothermal Atomic Absorption Spectroscopy (ETAAS) was also chosen as comparison technique because of its well-established and tested robustness.

The problem related to the presence of Platinum Group Metals (PGMs) in the environment has raised much attention and great interest in the scientific community. This is due to the fact that the PGMs are widely used in various fields, such as anticancer drugs, jewels production, photographic operations, industrial catalysts, and especially autocatalytic converters. In the last case, their continuous use and deterioration implies a considerable release of these metals in the environment. It should be noted that the metals initially used in autocatalytic converters were platinum, palladium and rhodium, but in recent years such PGMs were gradually and partially replaced, or alloyed with osmium and especially ruthenium. Their addition in the manufacture of autocatalytic converters helps them withstand high temperatures and wear, thus increasing the product life. Thus, the increasing use of autocatalytic converters shows two decidedly conflictual effects on the environment: an evident and drastic reduction of the concentration levels of lead, and, at the same time, an equally evident and widespread increase of the PGMs concentration, and in particular of ruthenium, due to its increasing use in recent years. This work proposes a voltammetric method for the determination of ultra-trace ruthenium in environmental samples: airborne particulate matter, vegetables, superficial waters, mussels, clams and soils/sediments. To better validate the proposed analytical procedure, a critical comparison with spectroscopic measurements - electrothermal atomic absorption spectroscopy (ET- AAS) because of its well established and tested robustness - has been also carried out and discussed here. All the parameters of interest for the set-up of an analytical method, such as trueness and precision (accuracy), limit of detection and quantification, selectivity and, especially, sensitivity were taken into account.

In the environmental field and in the last decade, the scientific attention has been addressed to platinum group metals (PGMs) owing to their increasing concentration in all the environmental matrices. This is due to the increasing use of these metals in several fields as for example production of industrial catalysts, anticancer drugs, jewels, even if in any case the cause of their growing concentrations in the environment is consequence of the compelling employment of autocatalytic converters. In fact the incorrect use “stop and go” of these converters, with consequent deterioration and abrasion, certainly implies a considerable release in the environment of airborne particulate matter at high PGMs concentration, which results to be the greatest, if not the only, source of contamination of the various environmental matrices, i.e. superficial water, soils, sediments, vegetables and so on. Really, after the first massive use of platinum, palladium and rhodium in the production of autocatalytic converters, there has been a gradual reduction of these PGMs with consequent growing use of iridium, ruthenium and, especially, osmium. Indeed, in the last decade, and more and more frequently, osmium together with iridium has been employed as alloying with platinum, palladium and rhodium in the manufacturing of autocatalytic converters in order to withstand high temperature and high wear. In fact, osmium in particular is rarely used in its pure state, and it is instead considered an important alloying agent especially in high-wear applications, owing to its strong corrosion resistance even at very high temperatures. Thus, this work intends to propose voltammetric methods for the osmium determination at ultra-trace level concentration in environmental samples: airborne particulate matter, superficial waters, soils/sediments, vegetables, mussels, clams and algae. To better validate the proposed analytical procedures, a critical comparison with spectroscopic measurements — electro-thermal atomic absorption spectroscopy (ET–AAS) because of its well established and tested robustness — has been also carried out and discussed here, taking into account all the parameters of interest to set-up an analytical method, such as precision and trueness (that together give accuracy), limit of detection and quantification, selectivity and, especially, sensitivity.

A rapid diffusion of heavy metals as environmental contaminants has called the attention to their determination. Indeed, heavy metals, together with pesticides, are very dangerous pollutants owing to their bioaccumulation and toxicity. It is therefore necessary to determine these metals at trace and ultra-trace level especially in aquatic ecosystems to establish reasonable water quality criteria. Moreover, toxic metals accumulate in certain marine species and thus enter the aquatic food chain. In particular mussels and clams, but also oysters, shrimps, fish and algae, sequestrate and concentrate several metals from their aqueous environment, possibly becoming dangerous to human health in consequence of their consumption. In particular mussels, clams and oysters, being filtering organisms - an adult organism is able to filter also up to 4-5 L h-1, depending on its weight - they require particular attention and inspections before being sold on the market. In addition to this important and fundamental aspect of public health, the determination of heavy metals in mussels and clams, that are not only filtering organisms but also sessile species, can be usefully employed for bio-monitoring campaigns, that evaluate the long-term trend of the pollution load of an aquatic ecosystem, information that evidently cannot be provided by punctual determinations. For completely mapping environmental pollution, the sampling duration and cadence are very important. In our opinion, the use of bio-monitors (mussels and clams in the present case), just proposed by several authors, but certainly not scientifically supported, is possible only in the case of a long sampling plan. In any case, the metal determination in mussels and clams evidently must be accurate, reproducible and especially it must show very low limits of detection. The present work reports and discusses the different analytical methodologies for the voltammetric and spectroscopic determination of heavy metals (copper, lead, cadmium, zinc, mercury, arsenic, selenium, tin and antimony) in oysters, mussels and clams. A separate section will be dedicated to the analytical procedure for the determination in such organisms of new emerging anthropic polluting traffic-related pollutants, i.e., the platinum group metals (platinum, palladium, rhodium, osmium, ruthenium and iridium).