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At least 433 records · Page 24Linked to original sources
PubMed2001

Early clinical results: SOUNDTEC implantable hearing device phase II study.

OBJECTIVE: To assess the safety and efficacy of a new semi-implantable electromagnetic hearing device, the SOUNDTEC Direct Drive Hearing System (DDHS), and to compare its performance with that of subjects' previously worn, optimally fit hearing aids. Preliminary results for the first 10 subjects are presented. STUDY DESIGN: The protocol specified in the Investigational Device Exemption is used in this ongoing FDA phase II 100-subject multicenter clinical trial. METHODS: For baseline, each subject is tested wearing his or her own optimally fit hearing aid in the ear to be implanted. Six-month postoperative outcome measures using the SOUNDTEC DDHS are compared with the baseline. Multiple objective and subjective outcomes (as listed under Results) were measured. RESULTS: When compared with the subjects' optimally fit hearing aids, the SOUNDTEC DDHS provided an average improvement of 52% in functional gain (250-6000 Hz), 22% in aided thresholds, 3.8% for speech discrimination in quiet, 17% for speech in noise, 13.1% in articulation index scores, 28% in aided benefit, 27.3% in sound quality of speech, and a 16.7% increase in overall subject satisfaction. In addition, with the SOUNDTEC DDHS, subjects reported absence of acoustic feedback, little or no occlusive effects, and more natural sound perception. CONCLUSION: Analysis of data on the first 10 subjects using the SOUNDTEC DDHS indicates positive outcomes regarding safety and efficacy, although the small sample size is not sufficient to permit valid statistical inferences to be drawn from our preliminary data. Results also demonstrate improvement in performance compared with the subjects' optimally fit hearing aids and an improvement in quality of life as demonstrated by objective and subjective tests and measures.

Aged↗
PubMedDate not supplied

ALARA study of teaching effectiveness on reducing radiation exposure.

The purpose of this study was to measure the effectiveness of radiation safety instruction and the impact on radiation film badge levels. A convenience sample of 144 endoscopy nurses and technicians was pretested for radiation safety knowledge, given a course in radiation safety, and then posttested immediately after the course and then 6 months later. Radiation badges were analyzed for radiation exposure at preinstruction, 1 month postinstruction, and 6 months postinstruction. Results showed that the instruction was effective. There was only a slight decrease in radiation badge readings; the decrease, however, was not statistically significant.

Adult↗
PubMed1995

Results and expectations with image-integrated brainstem stereotactic biopsy.

BACKGROUND: The histologic diagnosis of an intrinsic brainstem tumor remains problematic due to controversies in methods of biopsy. Despite the widespread use of biopsy techniques, stereotactic brain stem biopsy has received limited attention due to potential morbidity and limited sample size. METHODS: To evaluate the safety and efficacy of brain stem stereotactic biopsy using a dedicated computed tomography (CT)-stereotactic operating room suite, we reviewed our outcomes in 40 consecutive patients over a 13-year interval. This study included patients with midbrain lesions (n = 20), pontine lesions (n = 18), and medullary lesions (n = 2). Midline lesions were approached via a coronal, transthalamic trajectory; lateral brain stem lesions usually were approached via a transcerebellar route. RESULTS: A histologic diagnosis was achieved in 38 patients (95%). All patients had an immediate, intraoperative, postbiopsy CT scan to check for hemorrhage (none occurred). Morbidity was limited to one patient (2.5%) who developed a transient diplopia; there was no mortality. CONCLUSIONS: Stereotactic biopsy for intrinsic brain stem lesions proved as safe and effective as biopsy in the supratentorial compartment. Using high-resolution stereotactic imaging, an appropriate intraparenchymal trajectory, limited sampling, and specific neuropathologic tests, stereotactic techniques within the brain stem were performed with low risk and high accuracy. Biopsy results facilitated specific management strategies for each patient.

Adolescent↗
PubMed2003

What are older people prepared to do to avoid falling? A qualitative study in London.

Falls prevention strategies form a significant part of recent government policy relating to older people. In this article we report a qualitative study to examine the extent to which older people are willing to adopt any of the following strategies in order to avoid falling; balance and lower limb strengthening exercises, home safety advice, and 'taking care'. A sample of community-dwelling inpatients who were more or less afraid of falling were interviewed. Some older people blamed their own unsafe behaviour rather than hazards in their home for falls, so taking care (moving slowly, holding on, being vigilant to and avoiding danger) was a widespread strategy. The benefits of exercise in falls prevention were poorly understood and there was little enthusiasm for exercising especially if it was perceived to be inappropriate in old age or painful. Awareness of home hazards and taking measures against them was common but home visits tended to be regarded as intrusive. Inadequate negotiation about adaptations was widespread and led to resentment and unwillingness to cooperate. Building on the widespread 'taking care' strategy may help educated older people in safe behaviour. Health professionals should encourage older people to exercise and when making home safety visits should confer with their clients, taking their preferences about adaptations into account.

Accidental Falls↗
PubMed1994

The effect of firm characteristics on truck accidents.

This paper expands an earlier analysis of the effect of firm characteristics and safety practices on truck accident rates. The sample size has been increased from 13,000 to 75,500. Negative binomial regressions are used in preference to the Poisson technique used previously. The current analysis confirms previous results, but provides important new insights into the safety implications of being a private carrier and hauling hazardous materials and the effect of having been in business for many years.

Accidents, Traffic↗
PubMed2005

Long-term safety of drospirenone-estradiol for hormone therapy: a randomized, double-blind, multicenter trial.

OBJECTIVE: The purpose of this multicenter, double-blind, randomized, parallel-group study was to determine the effect of thirteen 28-day cycles of drospirenone combined with estradiol, compared with estradiol alone, on the endometrium of postmenopausal women. DESIGN: Postmenopausal women not on hormone therapy but with an intact uterus were enrolled (N = 1,147); 1,142 were evaluated. Participants were randomly assigned to treatment with 1.0 mg of estradiol alone (E(2) monotherapy) or 1.0 mg of estradiol plus 0.5, 1.0, 2.0, or 3.0 mg of drospirenone (DRSP/E(2)). Endometrial biopsies were performed at baseline, at 7 months if indicated, and at study end in the 13th month. Safety was evaluated with peripheral blood samples for hematology, liver and renal function, and lipids, along with vital signs and interval medical evaluations. RESULTS: When compared with estradiol alone, combinations of drospirenone and estradiol were effective in protecting against endometrial hyperplasia. The probability of hyperplasia was 0.060 (95% CI, 0.043-0.078) for the E(2) monotherapy group, 0.007 for the 2-mg DRSP/E(2) group, and nonsignificant for the remaining drospirenone/estradiol groups. Endometrial bleeding decreased in all treatment groups over time. The combination of drospirenone and E(2) relieved menopausal symptoms and resulted in improvements in health-related quality-of-life measures. There were no significant adverse events, and effects on triglycerides, total cholesterol, and high-density lipoprotein cholesterol were positive. CONCLUSIONS: The use of drospirenone combined with estradiol provides protection against endometrial hyperplasia, reduces endometrial bleeding with time, and relieves menopausal symptoms. There were no safety issues and blood pressure was reduced in women with hypertension.

Adult↗
PubMed2004

Isocyanate exposures in autobody shop work: the SPRAY study.

Isocyanates, known to cause respiratory sensitization and asthma, are widely used in automotive refinishing where exposures to aliphatic polyisocyanates occur by both inhalation and skin contact. The work reported here, the characterization of isocyanate exposure in the autobody industry, was part of an epidemiologic study of workers in 37 autobody shops in Connecticut. This article describes workplaces, tasks, and controls, and outlines the frequency, duration, and intensity of isocyanate exposures. Personal air samples taken outside of respirators had median concentrations of 66.5 microg NCO/m3 for primer, 134.4 microg (NCO)/m3 for sealer, and 358.5 microg NCO/m3 for clearcoat. Forty-eight percent of primer, 66% of sealer, and 92% of clearcoat samples exceeded the United Kingdom Health and Safety Executive guideline for isocyanate, though none exceeded the National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit for monomer. Nonisocyanate-containing primers and sealers are used in more than half the shops, but nonisocyanate clearcoats are rare. Eighty-two percent of personal samples taken within a spray booth exceeded the U.K. guideline: 81% of those in downdraft spray booths, 74% in semidowndraft booths, and 92% in crossdraft booths. Only 8% of shops reported that spraying is done exclusively in spray booths. All painters wore some type of respirator. In 30% of shops, painters used supplied air respirators; the rest relied on half face organic vapor cartridge respirators with N95 overspray pads. All shops provided some type of gloves, usually latex, not recommended for isocyanate protection. Despite improvements in autobody shop materials, practices, and controls, there are still opportunities for substantial exposures to isocyanates.

Air Pollution, Indoor↗
PubMed1996

Drugs usage of drivers suspected of driving under the influence of alcohol and/or drugs. A study of one week's samples in 1979 and 1993 in Finland.

The extent of drug use among drivers suspected of driving under the influence of alcohol and/or drugs in Finland was studied. All blood samples submitted to the laboratory during 1 week in two study periods, in 1979 (n = 298) and 1993 (n = 332), were analyzed for alcohol and psychotropic drugs. Drugs classified as hazardous to traffic safety were detected in 7.0% of the samples in 1979 and 26.8% in 1993. Benzodiazepines were the most frequently found drugs in both years: 6.0% of the cases in 1979 and 22.9% in 1993. Illegal drugs were found in 4% of the cases in 1993. Of the samples tested, 296 in 1979 and 317 in 1993 were from drivers suspected of driving under the influence of alcohol only. In 1979 every fourteenth and in 1993 every fourth of these suspected drunken drivers had drugs in their blood. Drugs, other than alcohol, were found six times more often than expected by the police. The results indicate that the trend of drug use, multidrug use and drug abuse is increasing among cases suspected of driving under the influence of alcohol/drugs.

Accidents, Traffic↗
PubMed2006

Ways to improve the biosecurity of bovine semen.

Semen production and trade is a worldwide industry. A framework, based on international standards is awaiting international and national regulation. In the perspective of biosecurity of the final product, critical notes can be made according to the semen production regulation and product safety. Process description brings the obligatory health standards for the production bulls, collection and processing of semen, identification, registration, worldwide distribution and insemination into discussion. Test frequency, test quality and demands, way of sampling and test consistency can influence product safety. New scientific knowledge can influence the value of the regulation. Whether a country is free of notifiable disease should influence decisions regarding necessary tests for the production bulls. The biosecurity of the semen production process is influenced by several factors. The effectiveness of the antibiotics used is questionable. The extenders for cryopreservation added to the semen can affect product safety. The way materials and storage containers have to be disinfected must be clear. In modern industry, tracking and tracing is an important issue. Worldwide differences in ways of identification of straws do not benefit a proper identification and registration throughout the process. Regulation could help improve the transparency of production and trade. Before anything concerning biohazard is implemented in regulation, each rule should be thoroughly based on scientific research where possible and furthermore it must be possible to enforce the regulation. The effort it takes to enforce the regulation should be in balance with the benefit it provides. An approach to alter regulation quickly is advisable. To produce a safe product that is accepted for international trade is of vital interest for the survival of artificial insemination (AI) in cattle.

Animal Identification Systems↗
PubMed2003

Evaluation of the culture of safety: survey of clinicians and managers in an academic medical center.

BACKGROUND: Despite the emphasis on patient safety in health care, few organizations have evaluated the extent to which safety is a strategic priority or their culture supports patient safety. In response to the Institute of Medicine's report and to an organizational commitment to patient safety, we conducted a systematic assessment of safety at the Johns Hopkins Hospital (JHH) and, from this, developed a strategic plan to improve safety. The specific aims of this study were to evaluate the extent to which the culture supports patient safety at JHH and the extent to which safety is a strategic priority. METHODS: During July and August 2001 we implemented two surveys in disparate populations to assess patient safety. The Safety Climate Scale (SCS) was administered to a sample of physicians, nurses, pharmacists, and other ICU staff. SCS assesses perceptions of a strong and proactive organizational commitment to patient safety. The second survey instrument, called Strategies for Leadership (SLS), evaluated the extent to which safety was a strategic priority for the organization. This survey was administered to clinical and administrative leaders. RESULTS: We received 395 completed SCS surveys from 82% of the departments and 86% of the nursing units. Staff perceived that supervisors had a greater commitment to safety than senior leaders. Nurses had higher scores than physicians for perceptions of safety. Twenty three completed SLS surveys were received from 77% of the JHH Patient Safety Committee members and 50% of the JHH Management Committee members. Management Committee responses were more positive than Patient Safety Committee, indicating that management perceived safety efforts to be further developed. Strategic planning received the lowest scores from both committees. CONCLUSIONS: We believe this is one of the first large scale efforts to measure institutional culture of safety and then design improvements in health care. The survey results suggest that strategic planning of patient safety needs enhancement. Several efforts to improve our culture of safety were initiated based on these results, which should lead to measurable improvements in patient safety.

Academic Medical Centers↗
PubMed2001

Evaluating sharps safety devices: meeting OSHA's intent. Occupational Safety and Health Administration.

The Occupational Safety and Health Administration (OSHA) revised the Bloodborne Pathogen Standard and, on July 17, 2001, began enforcing the use of appropriate and effective sharps devices with engineered sharps-injury protection. OSHA requires employers to maintain a sharps-injury log that records, among other items, the type and brand of contaminated sharps device involved in each injury. Federal OSHA does not require needlestick injury rates to be calculated by brand or type of device. A sufficient sample size to show a valid comparison of safety devices, based on injury rates, is rarely feasible in a single facility outside of a formal research trial. Thus, calculations of injury rates should not be used by employers for product evaluations to compare the effectiveness of safety devices. This article provides examples of sample-size requirements for statistically valid comparisons, ranging from 100,000 to 4.5 million of each device, depending on study design, and expected reductions in needlestick injury rates.

Blood-Borne Pathogens↗
PubMed2003

Introduction: the goals of antimicrobial therapy.

Antimicrobial agents are generally evaluated in preclinical studies assessing in vitro activity, animal models demonstrating in vivo bacteriologic efficacy, and clinical trials primarily investigating safety and clinical efficacy. However, large sample sizes are required to detect any differences in outcomes between antimicrobials in clinical trials, and, generally, studies are powered to show only clinical equivalence. In addition, diagnosis is often based on clinical symptoms, rather than microbiological evidence of bacterial infection, and the patients most likely to have resistant pathogens are often excluded. Clinical efficacy can be achieved in some bacterial infections in which antimicrobials are suboptimal or even not prescribed. However, bacterial eradication maximizes clinical efficacy and may also reduce the development and spread of resistant organisms. The goal of antimicrobial therapy is, therefore, to eradicate bacteria at the site of infection. Bacterial eradication is not usually assessed as a primary endpoint within the limits of currently recommended clinical trial design. However, pharmacokinetic (PK) (serum concentration profiles, penetration to site of infection) and pharmacodynamic (PD) (susceptibility, concentration- versus time-dependent killing, post-antimicrobial effects) criteria can be used to predict bacteriologic efficacy. PK/PD predictions should be confirmed during all phases of antimicrobial development and throughout clinical use in response to changing patterns of resistance. A clear rationale for dose recommendations can be determined preclinically based on PK/PD parameters, and correlated with efficacy, safety and resistance endpoints in clinical trials. The duration of treatment and dose should be the shortest that will reliably eradicate the pathogen(s), and that is safe and well tolerated. Currently available agents vary significantly in their ability to achieve PK/PD parameters necessary for bacteriologic eradication. Recommendations for appropriate antimicrobial therapy should be based on PK/PD parameters, with the aim of achieving the maximum potential for eradication of both existing and emerging resistant pathogens.

Anti-Bacterial Agents↗
PubMed1998

Potential of endocervical lavage for cytogenetic investigation of fetal cells as determined by in situ hybridization.

Aims: Transcervical samples following endocervical lavage from 28 women undergoing pregnancy termination were analysed in terms of fetal cells content and suitability for in situ hybridization analysis. A non fluorescent protocol of hybridization coupled to specific cytological procedures was used for simultaneous recognition and investigation on syncitiotrophoblast fragments. Methods: A series of endocervical washings was randomised to cytobrushing samples. Cervical washings were performed using variable volumes of physiologic saline solution (2ml, 5ml, 10ml). Single target in situ hybridization for chromosomes 1 and 18 was applied for determining a model of efficiency. Syncitial cells were recognized by means of cytoplasmic and nuclear stainings obtained with Eosin G (Diff-Quik) and haematoxylin respectively. Results: When 5 - 10ml of sterile solution were flushed multiple fragments of syncitio-trophoblast were almost constantly recovered. Conversely using 2ml of flushing solution no syncitia at all could be retrieved. Fetal cells were collected only in 50% of cervical cytobrushing. The per cell hybridization efficiency was on average 50%. Following in situ hybridization, a normal number of signal-products (2) was found in all nuclei analysed. Conclusion: During endocervical washing the amount of volume used is a critical factor to allow successful recovery of fetal cells. By using 5 - 10 ml of injecting solution, enough fetal material was generally obtained from each individual to guarantee the cytogenetic investigation for two chromosomes. The use of Diff-Quik and haematoxylin staining coupled to bright-field microscope facilitate the recognition of syncitia among a highly heterogeneous population of maternal cells. Further studies are ongoing to prospectively evaluate safety of the transcervical approach for sampling and analysis of fetal cells.

Journal Article↗
PubMed2003

Development of a sampling train for arsenic in pyrolysis vapours resulting from pyrolysis of arsenic containing wood waste.

In the present study a sampling and analysis method for arsenic emissions during pyrolysis of arsenic containing wood, such as chromated copper arsenate (CCA) treated wood, has been developed. The procedure is based on the NIOSH (National Institute for Occupational Safety and Health) standard for arsenic trioxide sampling. Validation for this specific application is needed since pyrolysis of arsenic containing wood leads to a gas stream containing sticky tar compounds and aerosols. Validation was carried out through tube furnace experiments using both CCA treated wood and arsenic trioxide powder as input. The outlet of the tube furnace was coupled to a cooling section and sampling train. The sampling train consisted of one or more filter sections and impingers. Different combinations of filters (untreated or impregnated) and impingers, as well as different combinations of washing solutions were tested. The different units of the sampling train were analysed by inductively coupled plasma mass spectrometry (ICP-MS) in order to determine the distribution of arsenic over the different units. For the working conditions considered (pyrolysis at 350 degrees C for 20 minutes with a nitrogen flow rate of 100 Nl h(-1)) the combination of a quartz cooling tube and a cellulose ester membrane filter impregnated with a Na2CO3-glycerol solution was sufficient to capture the arsenic. Two extra impingers (the first one containing 50 ml HNO3 1 M in the case of CCA treated wood and 50 ml NaOH 0.1 M in the case of As2O3 and the second one containing 50 ml NaOH 0.1 M) were added downstream of the filter section as backup either in case of filter failure or to check whether all the arsenic released is captured by the cooling tube and filter.

Air Pollutants↗
PubMed2003

Biological safety assessment of docosahexaenoic acid supplementation in a randomized clinical trial for X-linked retinitis pigmentosa.

BACKGROUND: In a 4-year placebo-controlled trial to elevate blood docosahexaenoic acid levels in patients with X-linked retinitis pigmentosa (XLRP), the goal was to assess the potential benefit of docosahexaenoic acid supplementation in altering disease progression. However, docosahexaenoic acid (22:6omega3) is a highly unsaturated fatty acid and considered a target molecule for free-radical oxidative damage. Thus, nutritional provision of docosahexaenoic acid might lead to an increase in antioxidant stress. Additional concerns, such as decreased platelet aggregation, increased bleeding time, and alterations in lipoprotein cholesterol levels, have been reported in supplementation studies with long-chain polyunsaturates. OBJECTIVE: To assess the biological safety of long-term docosahexaenoic acid supplementation. DESIGN: Forty-four male patients (mean age, 16 years) enrolled in a randomized, double-masked, clinical trial and received docosahexaenoic acid, 400 mg/d, or placebo. Blood samples were collected every 6 months. Biological safety analysis included fatty acids, vitamin A and E concentrations, antioxidant capacity, platelet aggregation, alanine aminotransferase activity, and lipoprotein cholesterol and triglyceride profiles. RESULTS: Mean plasma docosahexaenoic acid levels were elevated 2.5-fold by supplementation compared with baseline. Patients receiving placebo capsules exhibited no change (P =.35) in plasma docosahexaenoic acid content. All adverse events reported were minor and equivalently distributed between groups. Plasma vitamin A concentrations remained unchanged during the trial. Mean plasma vitamin E concentrations were correlated with age (P =.005), such that as patients with XLRP matured, plasma vitamin E concentrations increased to approach normal values. There was a trend (P =.10) toward lower mean vitamin E concentrations in the docosahexaenoic acid-supplemented group after 4 years. Docosahexaenoic acid supplementation did not compromise plasma antioxidant capacity, platelet aggregation, liver function enzyme activity, or plasma lipoprotein lipid content in patients with XLRP. CONCLUSION: Long-term docosahexaenoic acid supplementation to patients with XLRP was associated with no identifiable safety risks in this 4-year clinical trial.

Adolescent↗
PubMed1990

Application of existing technology to meet increasing demands for automated sample handling.

As the clinical laboratory advances toward total automation, the marketplace is now demanding more-efficient sample-handling systems. These demands have arisen over a relatively short period of time, in part because of heightened concern over laboratory safety and the resulting manpower shortages. Adding sample-handling capabilities to existing instrumentation is often a challenge, because usually mechanical or system constraints are present that interfere. This challenge has been overcome in the DuPont Sample Management System (SMS), a second-generation general chemistry analyzer that incorporates the latest barcode and computer-interfacing technology. The development of the SMS system relies heavily on recent advances in technology, e.g., software modeling and computer-aided design. The SMS system includes a barcode scanner based on "charge-coupled device" technology, a random-access sample wheel, and new software that oversees the various functions.

Chemistry, Clinical↗
PubMed2003

Long-term effects of polyacrylamide hydrogel on human breast tissue.

Polyacrylamide hydrogel is an atoxic, stable, nonresorbable sterile watery gel consisting of approximately 2.5% cross-linked polyacrylamide and nonpyrogenic water. Polyacrylamide hydrogel is widely used in ophthalmic operations, drug treatment, food packaging products, and water purification. In the former Soviet Union, polyacrylamide hydrogel has been used in plastic and aesthetic surgery for more than 10 years, and Kiev City Hospital treats approximately 300 women a year for breast augmentation using the polyacrylamide hydrogel Interfall (Contura SA, Montreux, Switzerland). Capsule shrinkage following these injections has never been observed. The authors examined breast tissue samples from a total of 27 women who had polyacrylamide hydrogel injected at Kiev City Hospital up to 8 years and 10 months earlier. Age at operation, duration of polyacrylamide hydrogel implantation, history of possible side effects to the gel injection, other intercurrent diseases, the reason for present open breast operation, and breast palpation findings before operation were in each case compared with the histological findings on samples taken from breast tissue bordering the gel. The gel presented itself as a dark violet, homogenous mass with a rounded or ragged outline in large or medium-size deposits and as elongated strands, which mimicked the extracellular matrix, in small deposits. Histological findings of the breast tissue bordering the gel showed three different patterns: large collections of gel gave rise to a thick, soft-looking cellular membrane of macrophages and foreign-body giant cells; medium-size deposits were surrounded by just a thin layer of macrophages; and small deposits were not associated with any reaction in the surrounding tissue. Projections of the cellular soft membrane, known as granulomas, were seen in six patients. The granulomas were composed of macrophages, foreign-body giant cells, lymphocytes, and blood cells. A thin layer of fibrous connective tissue was occasionally present around the foreign-body membrane, but the thick fibrous capsule, which has been described in connection with silicone implants, was completely absent. The gel changes could be correlated to neither time since gel injection nor a history of recent injury or inflammation. It is concluded that the polyacrylamide hydrogel Interfall, which has been used in the former Soviet Union, is stable over time, nondegradable, confined to the breast, and diffusion and migration resistant. When the hydrogel is injected in medium-size or large quantities a cellular foreign-body reaction occurs, but in small amounts it is capable of splitting up individual connective tissue fibers and fat cells, substituting for the extracellular connective tissue matrix without eliciting any foreign-body reaction. As far as these data are concerned, polyacrylamide hydrogel is well tolerated by the breast and does not give rise to severe fibrosis, pain, or capsule shrinkage. However, to determine safety with more certainty, a larger sample size would be necessary.

Acrylic Resins↗
PubMed2006

Pure, single phase, high crystalline, chamfered-edge zeolite 4A synthesized from coal fly ash for use as a builder in detergents.

Single phase chamfered-edge zeolite 4A samples in pure form with a high crystallinity were synthesized by applying step-change of synthesis temperature during hydrothermal treatment of coal fly ash. The calcium binding capacity of these zeolite 4A samples (prepared from coal fly ash) and the commercial detergent grade zeolite 4A were tested for usage as a detergent builder. The results show that these zeolite 4A samples behaved similarly as the commercial one in removing calcium ions during the washing cycle. Moreover, from the leaching tests (evaluation of toxicological safety), the results show that these zeolite 4A samples leached the same elements (Sb, As, Se and Tl) as the commercial one with the concentrations in the same order of magnitude. This shows that the toxicological effect of the coal fly ash converted zeolite 4A was not worse than that of the commercial sample. Finally, economic and environmental aspects of converting coal fly ash to useful products were discussed.

Adsorption↗