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Lead exposure is harmful at any time in life, but pre-natal and early childhood exposures are particularly detrimental to cognitive development. In Bangladesh, multiple household-level lead exposures pose risks, including turmeric adulterated with lead chromate and food storage in lead-soldered cans. We developed and evaluated an intervention to reduce lead exposure among children and their caregivers in rural Bangladesh. We conducted formative research to inform theory-based behavioral recommendations. Lead exposure was one of several topics covered in the multi-component intervention focused on early child development. Community health workers (CHWs) delivered the lead component of the intervention during group sessions with pregnant women and mother-child dyads (

In the recent years, the pigment industry, as a mother industry in the field of color matching, has had many applications and has greatly contributed to the progress of other industries such as textile, dyeing, glazing, construction and industrial paints, compounding, etc. For more optimal use in different industries, paying enough attention to the physical and chemical properties of pigments would be necessary. One of the most effective research projects in this field is the investigation of the effect of ultrasound radiation on the applied properties of pigments. In this research, by irradiating different times of ultrasound on the samples of organic pigment (red 48:1) and inorganic pigments (lemon yellow TL210 and orange yellow TM110 lead chromate) in the aqueous phase, the practical and visible effects were investigated on them. After ultrasonic irradiation on the selected pigments, some color test strips were prepared in a specialized paint laboratory, and they were tested with a spectrophotometer and a graindometer. The results of this research showed the great effect of ultrasound radiation on the reduction of the size of pigment particles and the increase of the opacity and coverage of the pigment, and also the increase of its resistance to sunlight; nevertheless, other properties such as water test, alkaline and acid test and thermal resistance test were not affected by ultrasound. Simultaneous application of dispersant with ultrasound resulted in further improvement of the mentioned properties. Based on the results of this research, paint and pigment companies might use ultrasonic radiation with appropriate probes along with different dispersants in their production line so as to increase production efficiency.

The darkening of chromate-pigments, including chrome yellows (PbCr 1-x S x O 4), is a surface phenomenon affecting late 19th-early 20th c. paintings, such as those by Van Gogh. Exploring analytical strategies that contribute to a deep understanding of darkening is therefore significant for the long-term conservation of unique masterpieces. Here, we examined the capabilities of Cr K-edge XANES spectroscopy collected at the same time in X-ray fluorescence yield (XFY) and total electron yield (TEY) detection modes to selectively study the surface composition of darkened oil paint mock-ups composed of chrome yellow (PbCr 0.2 S 0.8 O 4) or potassium chromate. By discussing advantages and drawbacks in using XFY/TEY modes in relation to XFY µ-XANES analysis from sectioned samples, we aim at assessing if TEY-XANES spectroscopy: (i) is a selective surface method to determine the abundance of different Cr-species from paint fragments; (ii) can contribute to optimize the analytical strategy by limiting time consuming sample preparation procedures; (iii) can decrease the probability of radiation damage. [ABSTRACT FROM AUTHOR]

The interfacial barrier of charge transfer from semiconductors to cocatalysts means that the photogenerated charges cannot be fully utilized, especially for the challenging water oxidation reaction. Using cobalt cubane molecules (Co4O4) as water oxidation cocatalysts, we rationally assembled partially oxidized graphene (pGO), acting as a charge‐transfer mediator, on the hole‐accumulating {−101} facets of lead chromate (PbCrO4) crystal. The assembled pGO enables preferable immobilization of Co4O4 molecules on the {−101} facets of the PbCrO4 crystal, which is favorable for the photogenerated holes transferring from PbCrO4 to Co4O4 molecules. The surface charge‐transfer efficiency of PbCrO4 was boosted by selective assembly of pGO between PbCrO4 and Co4O4 molecules. An apparent quantum efficiency for photocatalytic water oxidation on the Co4O4/pGO/PbCrO4 photocatalyst exceeded 10 % at 500 nm. This strategy of rationally assembling charge‐transfer mediator provides a feasible method for acceleration of charge transfer and utilization in semiconductor photocatalysis. [ABSTRACT FROM AUTHOR]

Coatings have been used since time immemorial for decorative and protective purposes. During the initial periods, when not much information was available regarding the health impact of the raw materials, there was no thought given or restrictions put on use of any ingredients in coatings. Some of the raw materials like white lead (lead carbonate), red lead (lead oxide), hexavalent chromium compounds, and other similar compounds were being used in large quantities to get specific paint film properties. This not only affected human health but also with no effective effluent treatment contaminated soil and water resources. With progress in technology and diagnostics, lead and chromium compounds have been identified as carcinogens. The developed countries (Europe and USA) were the first to ban the use of lead in their products in the 1970s and 1980s, but due to mainly economic reasons, these are still being used in the developing countries. As the long-term health impact is too much to bear, regulations/legislations have been enacted by the governments restricting use of lead/chrome in paints. The Global Alliance to Eliminate Lead Paint (GAELP), a joint association formed under the United Nations Environment programme, and World Health Organization have agreed to phase out manufacture and sale of paints containing lead by 2020. Similar restrictions exist for many other compounds used in coatings. The article attempts to present a synopsis of the history of coatings composition, impact of the heavy metals on health and environment, and the options available for shifting to safer coating composition. As major focus of the world is on lead elimination, it has been covered in more detail, but the article also provides information on other metals, namely cadmium, chromium, mercury, arsenic, antimony, tin, nickel, manganese, cobalt, etc., and their current status. [ABSTRACT FROM AUTHOR]

A crucial issue in artificial photosynthesis is how to modulate the behaviors of photogenerated charges of semiconductor photocatalysts. Here, using lead chromate (PbCrO4) as an example, we conducted the morphology tailoring from parallelepiped (p‐PbCrO4) to truncated decahedron (t‐PbCrO4) and elongated rhombic (r‐PbCrO4), resulting in exposed anisotropic facets. The spatial separation of photogenerated charges closely correlates to the anisotropic facets of crystals, which can only be realized for t‐PbCrO4 and r‐PbCrO4. The charge‐separation efficiencies exhibit a quasilinear relation with the surface photovoltage difference between anisotropic facets. The r‐PbCrO4 gives an apparent quantum efficiency of 6.5 % at 500 nm for photocatalytic water oxidation using Fe3+ ions as electron acceptors. Moreover, the oxidation reverse reaction from Fe2+ to Fe3+ ions was completely blocked with ∼100 % of Fe3+ conversion achieved on the anisotropic PbCrO4 crystals. [ABSTRACT FROM AUTHOR]

A rebuttal to "Reply to road markings and microplastics- a critical literature review" by Järlskog et al. is necessary because authors of the "Reply..." simultaneously agree with the major issues raised in the review and try to discredit it through presenting a different perspective; thus, clarifications of some key issues are due. In response to "binders derived from, e.g., modified rosin oils are still polymers" ("Reply...", p. 3), to confirm our claim that such materials are not necessarily polymeric, we are providing a Gel Permeation Chromatography spectrum of an esterified rosin designed for the use as a binder in thermoplastic road markings. Hence, while the value of the "Reply..." is in highlighting differences in definitions, it is unfortunate that no new knowledge about microplastics originating from road markings was provided and none of the multiple research needs and uncertainties were clarified. [ABSTRACT FROM AUTHOR]

Background: Hexavalent chromium compounds are sensitizers of the skin and lung. Chronic exposure to hexavalent chromium compounds is associated with respiratory effects and ulceration and perforation of the nasal septum. Such compounds are also considered carcinogens of the lung and nasal and paranasal sinus. Objectives: To demonstrate the importance of studying occupational and non-occupational exposure when assessing the concentration of substances in the urine. Case study: A study was conducted of environmental chromium concentrations in the workplace. In addition, an occupational medical examination was performed, recording activities inside and outside the workplace, eating habits, blood lead and urine chromium at the beginning and end of the workday. Results: One worker exposed to lead chromate presented high chromium concentrations in urine (up to 62 µg/l before the working day and 52 µg/l at the end of the working day). Environmental chromium concentrations in the workplace were below 0.25 µg/m3. In view of the results, a full study was conducted of the patient’s habits outside work. He reported having bought a kilo of a medicinal herb infusion at a street market three weeks previously. The concentration of total chromium in the prepared infusion was 12000 µg/l. The patient stopped consuming the medicinal herb. Subsequently, the urine chromium analysis was below 0.5 µg/l. Discussion and Conclusions: This case is interesting because it demonstrates that the consumption of medicinal herbs can interfere with biological monitoring of workers exposed to hexavalent chromium compounds. This may give rise to confusion and can also create legal problems for companies and workers. It is important to provide advice to workers and to investigate their habits outside work, especially when there is a discrepancy between environmental and biological values. In this case, the increase in urinary chromium is due to the consumption of medicinal herbs.

The paper examines the problem of the composition instability in the ready ground spice, turmeric. Analysis of the prevalent methods for turmeric adulteration and substances used for these purposes is given. The visual assessment of color tints of the turmeric root, spices containing it and chemical dyes based on chromium salts is presented. The studies on determination of the lead and chromium content were carried out to study the content of these metals and test the hypothesis of using lead chromate as a dye in adulteration of turmeric. Using the method of electrothermal atomic absorption spectroscopy, it was found that the lead content in the analyzed turmeric samples varied from 1.72 ± 0.58 to 5.03 ± 1.80 mg/kg, while the chromium content was in a range of 5.56 ± 0.85 to 16.15 ± 2.32 mg/kg. As a result of species specific PCR, wheat DNA was revealed in all purchased samples of ground turmeric. The levels of the main raw material replacement were established, which were 0.14% to 14.95% with the correlation coefficient close to 100%; efficiency of the reaction was 1.95, which was 97.5% when expressed as percentage. These levels of an undeclared allergen in the product composition can cause a serious allergic reaction. The authors tested the hypothesis of introduction of sodium and potassium salts for correction of the color spectrum in the ready spice and its correspondence to the natural color within the color spectrum of turmeric. As a result of the complex study of the spice composition, quite high values of chromium were found, presumably not only from the lead chromate compound but also from chromic acid salts, as the high level of potassium that significantly exceeded the native content of this element was found.

Spice adulteration using yellow lead chromate-based pigments has been documented as a growing global health concern. Spices from the Republic of Georgia with extremely high levels of lead, up to an order of magnitude higher than any other spices worldwide, have been implicated as sources of child lead poisoning. The objectives of this study were to 1) evaluate lead concentrations in spices sampled across the country of Georgia between 2020 and 2022, and 2) assess factors associated with spice adulteration, specifically the role of spice quality and regulatory enforcement. Spice samples were collected from 29 cities nationwide. The most populous cities were selected in each administrative region as well as those of importance to the spice supply chain. Sampling was carried out at the largest spice bazaars in each city. The regions of Adjara and Imereti were the focus of qualitative interviews conducted in 2021 with key businesspeople selling spices with very high and low levels of lead. The same cities and bazaars were visited at each of three sampling periods between 2020 and 2022. In total, 765 spice samples were collected. Lead concentrations in spices decreased over time, with a maximum of 14,233 μg/g in 2020 down to 36 μg/g in the final sampling round of 2022. A logistic regression determined that sampling round, region and spice type were associated with elevated lead in samples. Samples from Adjara and those containing marigold had the highest lead levels. Interviews with eighteen prominent spice vendors revealed difficulties sourcing sufficient quantities of high quality, brightly colored marigold, and concerns about adulteration. Interviews with two authorities from the National Food Authority highlighted the increased attention on regulating lead in spices since 2018. Continued monitoring and periodic regulatory enforcement may adequately disincentivize further adulteration with lead chromate in the spice industry in Georgia. • Changes in nationwide spice lead levels are assessed in the Republic of Georgia. • Incentives driving lead chromate adulteration of spices are assessed. • Spice lead levels varied by spice type and region. • Spice lead levels decreased nationwide between 2020 and 2022. • Environmental contamination may contribute to spice lead levels above regulatory limits. [ABSTRACT FROM AUTHOR]

Although lead (Pb) paint testing has been carried out in a large number of studies in Sri Lanka, little work appears to have been done to investigate the chromium (Cr) levels, variation of Pb and Cr levels through different production batches of paint manufacturers and the possible sources of unusually higher Pb and Cr levels in paints. Thirty-six enamel paints manufactured after the lead paint regulatory enforcement, were randomly purchased from six popular brands in Sri Lanka to assess their Pb and Cr levels. Heavy metals in liquid paints were acid digested for the analysis by flame atomic absorption spectrometry (FAAS). From the thirty-six paints analysed (six colours from six brands) one yellow and one green paint showed highest Pb and Cr levels. Reported Pb levels in yellow and green paints were 11545 ± 6 ppm and 4060 ± 9 ppm and Cr levels were 2681 ± 2 ppm and 960 ± 7 ppm, respectively. These yellow and green paints were labelled as safe although they exceeded the Pb regulatory limit. Pb and Cr in the other 34 samples were below Sri Lankan regulatory limits. For paints with both Pb and Cr, Pb and Cr mole ratio was 1.079:1, suggesting the possible presence of lead chromate (PbCrO4) in certain paints although the manufactured paints adhered to safety standards. Batch-wise manufacturing variation was also reported. Thus, formulation of national policies and their proper implementation is necessary for manufacturing safe paints in Sri Lanka. [ABSTRACT FROM AUTHOR]

The majority of the studied artworks were altarpieces, sculptures and/or wood-based works from different periods. Non-traditional gilding techniques have been first described in this paper, such as those that employ materials as oil in the gilding on bole, glue and bole with lead white in mordant gilding, vermilion in the preparation layers; and brass gilding or those with aluminium, lead chromate, mica or corla trying to imitate the golden hue in restoration or repaint processes. For the determination of the composition of the different gilded layers, spectroscopic techniques, such as FTIR and micro-Raman, and SEM-EDX elemental chemical analyses were successfully used. [ABSTRACT FROM AUTHOR]

Lead sulfate was chose to precipitate chromium (VI) based on the difference of the solubility between lead sulfate and lead chromate. The effects of parameters on the precipitation efficiency of chromium including reaction temperature, reaction time, and initial pH of solution and dosage of lead sulfate were investigated. Results showed that the initial pH of solution and dosage of lead sulfate had big influence while reaction time and reaction temperature had little. The concentration of chromium (VI) could reduce from 0.2 mol/L to 0.0015 mmol/L (0.08 mg/L) at pH value of 13.90 and the dosage of lead sulfate as n (PbSO 4 )/ n (K 2 CrO 4 ) = 4. The XRD result of precipitation was consistent with the result predicted by Visual MINTEQ software and the precipitation was composed of PbCrO 4 , PbSO 4 and other oxides containing lead. Otherwise, XRF and ICP were used to analyze the residual lead (II) in the filtrate and results indicated that the concentration of Pb (II) in the filtrate was acceptable. [ABSTRACT FROM AUTHOR]

Turmeric adulterated with lead chromate pigment has been previously identified as a primary source of lead exposure in Bangladesh. This study assesses the impact of a multi-faceted intervention between 2017 and 2021 to reduce lead-tainted turmeric in Bangladesh. The intervention involved: i) disseminating findings from scientific studies via news media that identified turmeric as a source of lead poisoning, ii) educating consumers and businesspeople about the risks of lead chromate in turmeric via public notices and face-to-face meetings, and iii) collaborating with the Bangladesh Food Safety Authority to utilize a rapid lead detection technology to enforce policy disallowing turmeric adulteration. Before and after the intervention, evidence of lead chromate turmeric adulteration was assessed at the nation's largest turmeric wholesale market and at turmeric polishing mills across the country. Blood lead levels of workers at two mills were also assessed. Forty-seven interviews were conducted with consumers, businesspeople, and government officials to assess changes in supply, demand, and regulatory capacity. The proportion of market turmeric samples containing detectable lead decreased from 47% pre-intervention in 2019 to 0% in 2021 (n = 631, p < 0.0001). The proportion of mills with direct evidence of lead chromate adulteration (pigment on-site) decreased from 30% pre-intervention in 2017 to 0% in 2021 (n = 33, p < 0.0001). Blood lead levels dropped a median of 30% (IQR: 21–43%), while the 90th percentile dropped 49% from 18.2 μg/dL to 9.2 μg/dL 16 months after the intervention (n = 15, p = 0.033). Media attention, credible information, rapid lead detection tools and swift government action to enforce penalties all contributed to the intervention's success. Subsequent efforts should evaluate if this is an example of an effective intervention that can be replicated to reduce lead chromate adulteration of spices globally. • The impact of an intervention to reduce lead in turmeric in Bangladesh is assessed. • The percent of market turmeric samples containing lead decreased from 47% to 0%. • The percent of mills adding lead chromate to turmeric decreased from 30% to 0%. • Turmeric mill worker blood lead levels dropped a median of 30% (IQR: 21–43%). • Future research should evaluate if this intervention can be replicated elsewhere. [ABSTRACT FROM AUTHOR]

In the past, chrome yellow (lead chromate, PbCrO4), a bright orange-red substance, has been widely used as an inorganic pigment in the production of paints, coatings, and plastics. Herein, we demonstrate that laser desorption/ionization mass spectrometry (LDI-MS) is a powerful tool for the detection of lead chromate in solid residues. In fact, lead chromate in trace amounts is easily detectable by LDI-MS even from residues left as latent prints. For example, a latent print obtained by stamping the exposed laterally cut surface of a pencil over 50 years old on an acetonitrile-moistened paper, was successfully imaged for both lead and chromate using a Synapt G2 HDMS mass spectrometer. After rastering the print with a 355nm laser beam and recording positive- and negative-ion mass spectra over the range m/z 50-1200, we generated false-color 'heat maps' (single-ion images) for 208Pb+· (m/z 207.98) and Cr2O6 -· (m/z 199.85). The heat maps matched closely with the faint visual image of the pencil imprint. Moreover, our results confirmed that lead chromate was used in the pigment coatings of old pencils. Evidently, LDI-MS imaging is an efficient procedure to survey for the presence of lead and chromate in minerals and other materials. [ABSTRACT FROM AUTHOR]

The Winsor & NewtonTM(W&N) nineteenth century archive database includes digitised images of hand-written instructions and workshop notes for the manufacture of their artists’ materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types:lemon/palebased on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O4];middleon pure monoclinic lead chromate [PbCrO4]; anddeepthat contains the latter admixed with basic lead chromate [Pb2CrO5]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale’ and ‘lemon’ correlated with the pigment in their tube labelledchrome yellowand, ‘middle’ and ‘deep’ with the labelchrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed. [ABSTRACT FROM PUBLISHER]

This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x≈0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., CrIII compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future. [ABSTRACT FROM AUTHOR]