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PubMed2001

Effect of pre-treatment on the surface and electrochemical properties of screen-printed carbon paste electrodes.

The effect of various electrochemical pre-treatment methods on the surface and electrochemical properties of screen-printed carbon paste electrodes (SPCE) prepared with three different commercial products was examined. It was observed that a positively charged redox couple, e.g., hexaammineruthenium(III), exhibited quasi-reversible behavior at the untreated SPCE. However, the cyclic voltammograms (CVs) of the SPCE prepared with general-purpose carbon inks did not exhibit clear redox peaks to other representative redox couples [e.g., hexacyanoferrate(III), hexachloroiridate(IV), dopamine, and hydroquinone] without activation. Electrochemical pre-treatment methods were sought in four different aqueous solutions, i.e., sulfuric acid, potassium chloride, sodium hydrogencarbonate, and sodium carbonate, applying various activation potentials. It was found that the pre-treatment procedure in saturated Na2CO3 solution at 1.2 V provides a mild and effective condition for activating the SPCE. By measuring the water contact angles at the SPCE surfaces and recording their SEM images, it was confirmed that the electrochemical pre-treatment effectively removes the organic binders from the surface carbon particles. A prolonged period of activation (> 5 min) or the use of high potentials (> 1.2 V) increased the capacitance of the electrode over 20 microF cm(-2). The pre-treated SPCE behaved like a random array microelectrode, exhibiting a sigmoidal-shaped CV at a slow scan rate. The short pre-anodization method in Na2CO3 solution was generally applicable to most SPCE prepared with general-purpose carbon inks.

Journal Article↗
PubMed2004

Fabrication of carbon microelectrodes with a micromolding technique and their use in microchip-based flow analyses.

In this paper, we report a new technique to pattern carbon microelectrodes for use in microfluidics. This technique, termed micromolding of carbon inks, uses poly(dimethylsiloxane)(PDMS) microchannels to define the size of the microelectrode. First, PDMS microchannels of the approximate dimensions desired for the microelectrode are made by soft lithography. The PDMS is then reversibly sealed to a substrate and the microchannels are filled with carbon ink. After a heating step the PDMS mold is removed, leaving a carbon microelectrode with a size slightly smaller than the original PDMS microchannel. The resulting microelectrode (27 microm wide and 6 microm in height) can be reversibly sealed to a PDMS-based flow channel. Fluorescence microscopy showed that no leakage occurred around the chip/electrode seal, even up to flow rates of 10 microL min(-1). The electrode was characterized by microchip-based flow injection analysis. Injections of catechol in Hank's Balanced Salt Solution (pH 7.4), showed a linear response from 2 mM to 10 microM (r(2)= 0.995), with a sensitivity of 56.5 pA microM(-1) and an estimated limit of detection of 2 microM (0.27 picomole, S/N=3). Reproducibility of the electrode response was shown by repeated injections (n= 10) of a 500 microM catechol solution, resulting in a RSD of 4.6%. Finally, selectivity was demonstrated by coating the microelectrode with Nafion, a perfluoronated cation exchange polymer. Dopamine exhibited a response at the modified microelectrode while ascorbic acid was rejected by the Nafion-coating. These electrodes provide inexpensive detectors for microfluidic applications while also being viable alternatives to use of other carbon microelectrode materials, such as carbon fibers. Furthermore, the manner in which the microelectrodes are produced will be of interest to researchers who do not have access to state of the art microfabrication facilities.

Carbon↗
PubMed2000

Ability of anaesthetists to identify a marked lumbar interspace.

Anaesthetists' ability to identify correctly a marked lumbar interspace was assessed in 100 patients undergoing spinal magnetic resonance imaging scans. Using ink, one anaesthetist marked an interspace on the lower spine and attempted to identify its level with the patient in the sitting position. A second anaesthetist attempted to identify the level with the patient in the flexed lateral position. A marker capsule was taped over the ink mark and a routine scan performed. The actual level of markers ranged from one space below to four spaces above the level at which the anaesthetist believed it to be. The marker was one space higher than assumed in 51% of cases and was identified correctly in only 29%. Accuracy was unaffected by patient position (sitting or lateral), although it was impaired by obesity (p = 0.001) and positioning of the markers high on the lower back (p < 0.001). The spinal cord terminated below L(1) in 19% of patients. This, together with the risk of accidentally selecting a higher interspace than intended for intrathecal injection, implies that spinal cord trauma is more likely when higher interspaces are selected.

Adult↗
PubMed1997

Microleakage of Diaket and amalgam in root-end cavities prepared using MicroMega sonic retro-prep tips.

The in vitro sealing ability of the root-canal sealer Diaket when used as a root-end filling material was compared with that of amalgam using linear micro-leakage of Indian ink. Eight groups of 20 extracted teeth each were formed, plus 12 control teeth as follows: 1) root-end resection of 45 degrees bevel, root-end cavity preparation with an 008 round bur, amalgam root-end filling; 2) 45 degrees bevel, bur, Diaket; 3) 45 degrees bevel, using a sonic retro-prep tip, amalgam; 4) 45 degrees bevel, sonic, Diaket; 5) no bevel, bur, amalgam; 6) no bevel, bur, Diaket; 7) no bevel, sonic, amalgam; 8) no bevel, sonic, Diaket. Root-end cavity depths of 3 mm were prepared. Specimens were immersed in Indian ink for 2 weeks. The teeth were demineralized, rendered transparent and linear dye penetration recorded. Results showed that Diaket provided a superior seal to amalgam irrespective of the root-end preparation. The degree of bevel of the resected root-end did not influence leakage. Sonic instrumentation resulted in a larger root-end cavity than with burs.

Apicoectomy↗
PubMed1998

Sealing ability of composite resin placed over calcium hydroxide and calcium sulphate plugs in the repair of furcation perforations in mandibular molars: a study in vitro.

The purpose of this study was to evaluate in vitro the sealing ability of various materials in the repair of furcation perforations in mandibular molars by measuring coronal microleakage with Indian ink. Ninety extracted mandibular molars were embedded individually into a plaster of Paris block, with the roots surrounded by a simulated periodontal ligament of silicone. Subsequently, a standard coronal access opening was prepared, the root canal orifices were located and a perforation was made with a size 012 round bur in a water-cooled high-speed handpiece directly into the centre of the floor of the pulp chamber. The perforations were repaired with amalgam, composite resin, calcium sulphate under composite resin and calcium hydroxide under composite resin. The teeth were coated with two layers of nail polish, leaving the access opening area uncovered, and immersed in Indian ink for 4 days at 37 degrees C. The teeth were sectioned longitudinally and dye penetration measured from the coronal level of the repair material to the apical end of the perforation. All experimental groups revealed dye penetration in varying degrees, but there was no significant difference amongst them (Kruskal-Wallis test P < 0.05). Calcium sulphate and calcium hydroxide prevented overextrusion of composite resin when used under this repair material.

Analysis of Variance↗
PubMed2001

Coronal leakage following three obturation techniques.

AIM: To compare coronal bacterial and India ink leakage in three different obturation techniques with the smear layer having been removed. METHODOLOGY: Seventy extracted single-rooted teeth were instrumented to an apical preparation size 7 Profile Series 29 (Tulsa Dental Products, Tulsa, OK, USA). The smear layer was removed and 20 teeth were randomly obturated with lateral compaction, 20 teeth with vertical compaction, and 20 teeth with Thermafil (Tulsa Dental Products, Tulsa OK, USA). Ten teeth were used for positive (five teeth) and negative (five teeth) controls. Teeth were stored for 90 days in 100% humidity, then subjected coronally to Proteus vulgaris for 21 days to assess bacterial leakage. Following bacterial challenge, India ink was placed coronally for a further 21 days, then scored according to depth of dye leakage. RESULTS: Vertical compaction leaked significantly less than lateral compaction during bacterial challenge. However, when dye was used there were no significant differences. CONCLUSIONS: Bacterial leakage and dye leakage demonstrated considerable variability. The use of a dye following bacterial testing may highlight the failure of experimental devices and vertical root fractures, thus avoiding false positive results found with bacterial testing alone.

Carbon↗
PubMed2000

Aspects of the functional morphology of the ductus epididymidis in domestic anseriform and galliform birds.

The structure of the ductus epididymidis, and its capacity to take up luminal particulate material (India ink) were studied, using scanning and transmission electron microscopy, in the domestic fowl, turkey and Japanese quail (Order Galliformes) and drake (Order Anseriformes). The epithelium appeared contractile and stable structurally, especially in the drake in which, among other cytoskeletal features, abundant perinuclear intermediate filaments radiated peripherally in the principal, nonciliated (Type III) cell. The Golgi complex was well developed, except in the turkey in which it was extremely inconspicuous. Sparsely granulated profiles were the main component of the elaborate endoplasmic reticulum, which was best developed in the drake and least in the turkey. The cell in the turkey was uniquely laden with large aggregates of lipid droplets. Generally, characteristics of a cell active in the synthesis and merocrine secretion of proteinaceous material were evident. There was no evidence of apocrine-like secretion in well-fixed tissues. The cell lacked the capacity to take up luminal India ink particles, and displayed very poorly developed endocytic structural features, which are also probably only selectively and minimally absorptive. Ultrastructural features varied between and within the orders studied, necessitating further studies.

Animals↗
PubMed1997

Angiogenesis at the site of neuroma formation in transected peripheral nerve.

Investiture of new microvessels within an injured peripheral nerve trunk may determine the success that the local environment has in promoting axonal sprouting and regeneration. We therefore examined microvessel investment of 24 h-14 d proximal nerve stump preparations in rat sciatic nerves. The stumps, later destined to form neuromas, were created by sciatic nerve transection with resection of distal branches to prevent distal reinnervation. Microvessels were studied in the proximal stump in semithin whole mount sections of nerve and by analysis of India ink perfused microvessel profiles. Quantitative image analysis was made of the luminal profiles of vessels perfused with India ink from unfixed sections of the stumps, contralateral uninjured nerves and sham-exposed but uninjured nerves. Evidence of angiogenesis was observed in stumps 7 d after transection, indicated by a rise in the total numbers of perfused microvessels and in the numbers of 2-6 microns diameter perfused microvessels. There was a shift in the histogram of the percentage of perfused microvessels towards the 2-4 microns range and a reduction in the mean microvessel luminal area in the stumps. By 14 d, new microvessels were larger, indicated by an increase in total luminal area. New microvessels were prominent in the epineurial connective tissue or between layers of perineurial cells of former fascicles. Microvessels probably share a battery of trophic signals with other proliferating cellular elements in the milieu of the injured peripheral nerve trunk.

Analysis of Variance↗
PubMed2000

Mohs surgery and processing: novel optimizations and enhancements.

OBJECTIVE: Simple yet effective modifications to Mohs surgery and processing may enhance procedural efficiency, ensure proper tissue orientation and tracking, while greatly reducing "recuts." Using the methods described, Mohs specimens no longer need to be incised or excised with any bevel, thus conserving tissue and facilitating closure. METHODS: A streamlined Mohs surgical tray is convertible to a closure tray within seconds. The excised tissue specimen is oriented on a sterile paper square on a reusable sterilized aluminum palette where partial thickness circumferential and radial scalpel cross-hatching allows epidermal edges complete freedom to later adhere to a flattening glass. The sterile paper can be labeled with patient name, stage number, and chuck number; then the specimen is inked. Rapid chuck freezing in a specially positioned liquid nitrogen immersion is followed by OCT (embedding compound) application. Uniquely numbered and modified cryostat chucks eliminate the possibility of OCT-chuck disunion. Rapid liquid nitrogen immersion of a glass surface allows the inked, cross-hatched specimen's epidermal edges and base to lay perfectly flat once forced against the supercooled glass surface using a special polymer glove. Inversion of the specimen-containing glass onto a frozen and gel state OCT interface of the chuck completes the embedding. RESULTS/CONCLUSION: These reproducible approaches to Mohs surgery described herein utilize multiple modifications that enhance the speed, efficiency, and reproducibility of Mohs specimen embedding, specimen preparation, while maintaining accuracy of interpretation.

Humans↗
PubMed2003

Efficacy of the flashlamp-pumped pulsed-dye laser in nonsurgical delay of skin flaps.

OBJECTIVE: The purpose of this article was to determine the effectiveness of laser delay by use of the flashlamp-pumped pulsed-dye laser operating at a wavelength of 585 nm; to elucidate the comparable or dissimilar macroscopic, microscopic, and hemodynamic changes between laser and surgical delay methods; and to clarify the possible mechanisms underlying the delay effect of laser. METHODS: A standardized caudally based random dorsal rat flap model was used in this study: Acute random skin flaps served as control subjects (group 1). Surgical delay was employed by incision of lateral longitudinal borders both without (group 2) and with (group 3) undermining, and laser delay methods were performed by laser irradiation of both lateral longitudinal borders (group 4) and the entire surface (group 5) of the proposed flap. Evaluation was done by histologic examination, India ink injection, laser Doppler perfusion imaging, and measurement of flap survival. RESULTS: Histologically, dilation and hypertrophy of subpapillary and subdermal vessels were evident in groups 2, 3, and 4; on the other hand, degranulation of mast cells in the vicinity of occluded vessels at the 1st hour of laser delay and a striking mast cell proliferation and degranulation in association with newly formed vessels (angiogenesis) at the 14th day of laser delay were prominent in group 5. India ink injections revealed longitudinally arranged large-caliber vessels and cross-filling between the vessels of adjacent territories in groups, 2, 3, and 4, but only small-caliber vessels in group 5. Compared with the acute flaps, both surgical and laser delay significantly increased the mean flap perfusion to the maximal levels after a 14-day delay period, and all delay procedures improved flap survival; the most significant increase in surviving area was observed in group 3, whereas the less significant increase in surviving area was in group 5. CONCLUSION: This study demonstrates that laser delay is as effective as surgical delay and that laser delay by lasering lateral borders leads to dilation and longitudinal rearrangement of the existing vessels rather than angiogenesis, whereas laser delay by lasering the entire surface results in delay effect by inducing angiogenesis due to activation and degranulation of the mast cells.

Animals↗
PubMedDate not supplied

Distribution of solution in the epidural space: examination by cryomicrotome section.

BACKGROUND AND OBJECTIVES: The routes of distribution and barriers to flow of solutions in the epidural space are incompletely determined. This study examined macroscopic details of epidural injectate spread in postmortem humans by cryomicrotome imaging. METHODS: Soon after death, 3 nonembalmed adult human subjects were injected with ink through epidural catheters inserted by standard techniques. Following freezing, microtome sectioning was performed to reveal anatomic features down to 100 microm. To control for effects of death, an adult baboon was injected during general anesthesia and subsequently examined in the same fashion. RESULTS: Injected ink was readily evident and showed spread as rivulets through numerous small channels rather than as a unified advancing front. The fascia that extends laterally from the posterior longitudinal ligament is an important barrier restricting solution flow. Solution preferentially traveled along the nerve root sheath through the intervertebral foramen. CONCLUSIONS: Distribution of solution in the epidural space is nonuniform. Rather than a uniform advancing front, spread is directed among paths between structures according to pressures by which they are compressed. No structural barriers block flow through the intervertebral foramina or spinal canal other than the fascia of the posterior longitudinal ligament.

Adult↗
PubMed2006

Indocyanine green is an ideal dye for endoscopic ultrasound-guided fine-needle tattooing of pancreatic tumors.

Endoscopic ultrasound-guided fine-needle tattooing (EUS-FNT) is an ideal technique for preoperative marking of lesions detected on preoperative examination. Although India ink has been used for endoscopic tattooing, there have been numerous reports of complications associated with its use. This is the first report of EUS-FNT using indocyanine green (ICG) and describes its use for preoperative marking of a tumor in a 78-year-old man with multiple pancreatic tumors. There were no complications associated with the EUS-FNT procedure and it is suggested that ICG is a more suitable dye for tattooing of pancreatic lesions than India ink, being far less frequently associated with side effects.

Aged↗
PubMed2001

Laryngeal compartmentalization after radiation therapy in a canine model.

OBJECTIVE: We set out to study the effects of radiation therapy on laryngeal tissue barriers in a canine model as described by Welsh. STUDY DESIGN: India ink was injected into 1 vocal fold on irradiated and nonirradiated canine larynges. RESULTS: The india ink dye spread more prominently into the supraglottis of the irradiated specimens by submucosal lymphatics. Larger dye volumes simulating larger tumor bulk spread to the contralateral larynx in irradiated specimens. CONCLUSION: Conservation laryngeal surgery for laryngeal carcinoma is a popular method of treatment. Some surgeons advocate partial laryngectomy for radiation failures; in other instances, it is the primary modality of treatment. These findings suggest a cautious approach when planning conservative laryngeal surgery after radiation therapy failures of glottic carcinoma.

Animals↗
PubMed2001

Quantitative analysis of intravitreal injections in the rat.

Intravitreal injections are currently used in the rat to introduce a therapeutic factor in the eye, especially for experimental treatments of retinal degenerations. The injected volume and its location can influence the quantification of results. We have investigated the quantitative effect of a single intravitreal injection in rats at different ages and for different volumes. Albinos rats aged three weeks or two months received intravitreal injections of 1, 3, 5 or 10 microl China ink. Animals were sacrificed immediately after injection, eyes were enucleated, fixated, embedded in paraffin and microtomy was performed in a sagittal plane. Regularly spaced sections were analyzed to reconstruct the vitreous and injected dye volumes. The measured vitreous volume was 6.76 +/- 0.37 mm(3) in three weeks old rats and 13.36 +/- 0.64 mm(3) in two months old rats. Mean intravitreal ink volumes immediately after injection were 0.8 mm(3) for 1 ml injections, 2 mm( 3) for 3 ml, 2.3 to 2.6 mm(3) for 5 microl and 3.2 mm(3 ) for 10 microl. The percentage of vitreous volume involved by the injection ranged from 4.4% to 33.2%. The injected volume is limited by the large lens size of the rat. Extraocular loss of injected solution increases for higher injected volumes, with larger standard deviations. In this model, the dye tends to localize behind the lens. A 3 or 5 microl volume appears to have the best reproducibility with minimum loss of solution.

Aging↗
PubMed2002

Toxicity testing and chemical analyses of recycled fibre-based paper for food contact.

Food-contact materials, including paper, have to comply with a basic set of criteria concerning safety. This means that paper for food contact should not give rise to migration of components, which can endanger human health. The objectives of this pilot study were, first, to compare paper of different qualities as food-contact materials and to perform a preliminary evaluation of their suitability, from a safety point of view, and, second, to evaluate the use of different in vitro toxicity tests for screening of paper and board. Paper produced from three different categories of recycled fibres (B-D) and a raw material produced from virgin fibres (A) were obtained from industry, and extracts were examined by chemical analyses and diverse in vitro toxicity test systems. The products tested were either based on different raw materials or different treatments were applied. Paper category B was made from 40% virgin fibres, 40% unprinted cuttings from newspapers, and 20% de-inked newspapers and magazines. Paper categories C and D were based on newspapers and magazines. However, paper D was de-inked, whereas C was not. To identify constituents of the papers with a potential to migrate into foodstuff, samples of the paper products were extracted with either 99% ethanol or water. Potential migrants in the extracts were identified and semiquantified by GC-IR-MS or GC-HRMS. In parallel to the chemical analyses, a battery of four different in vitro toxicity tests with different endpoints were applied to the same extracts. (1) a cytotoxicity test using normal human skin fibroblasts. The test was based on measurements of the reduction of resazurin to resorufin by cellular redox processes and used as a screening test for acute or general toxicity; (2) a Salmonella/microsome assay (Ames test) as a screening test for mutagenic and potentially carcinogenic compounds; (3) a recombinant yeast cell bioassay as a screening test for compounds with oestrogenic activity; (4) an aryl hydrocarbon (Ah)-receptor assay (CALUX assay) as a screening test for compounds with dioxin-like activity. In addition, the papers were testedfor microbial content and, in general, the microbiological load was quite low. The following microorganisms were counted and identified on both surface and homogenized pulp samples: the total number of aerobic bacteria, the number of aerobic and anaerobic spore formers, the number of Bacillus cereus/thuringiensis, and the number of yeast and moulds. The chemical analyses showed a significantly higher amount and different composition pattern of chemicals extracted with ethanol compared with water. Analyses of the ethanol extracts showed a distinctly smaller number and lower concentrations of chemicals in extracts prepared from sample A compared with extracts of samples B-D. The compounds identified in B-D were similar, but the amounts were lower in B compared with C and D. In accordance with the chemical analyses, the water extracts were less cytotoxic than the ethanol extracts. The extract prepared from virgin fibres was less cytotoxic than the extracts prepared from paper made from recycled fibres, and extracts prepared from C was the most cytotoxic. None of the extracts showed mutagenic activity. No conclusion about the oestrogenic activity could be made, because all extracts were cytotoxic to the test organism (yeast cells). Ethanol extracts of A and B showed a negligible positive response in the Ah-receptor assay at the highest nontoxic concentration, whereas C and D showed a more pronounced effect with C being the most potent. A comparable weak effect of water extracts of samples B-D was observed, too. However, the active compound(s) was not identified by chemical analyses.

Biological Assay↗
PubMed2005

The relation between narrow-dispersed microcapsules and surfactants.

Electric ink display is one of the prospect technologies in paper-like display. In this paper, electric ink microcapsules are prepared by means of an in situ polymerization and complex coacervation. In order to obtain the microcapsules in a uniform size distribution, this study focused on the inter-facial tension between tetrachloroethylene and water solution, the dispersion of the core droplets and the microencapsulation with different kind of surfactants. By measuring the inter-facial tensions between water and tetrachloroethylene, it is found that urea-formaldehyde (UF) pre-polymer presents certain surface activity due to the inter-facial tension descending from 43 mN m(-1) to 35 mN m(-1). Because the surface activity of pre-polymer is not valid, the water-soluble emulsifiers can occupy on the surface of the droplets and prevent the UF resin depositing there. The analysis of the size distribution shows that the UF microcapsules are multi-dispersed. Furthermore, the influence of anionic surfactant of SDS on the size distribution of the core droplets is also investigated. The average diameters of the core droplets prepared with 0.005 wt% and 0.012 wt% SDS are approximately 50 microm and 28 microm, respectively. That reveals the existence of SDS not only decreases the droplet diameters, but also makes the size distribution centralized. Because the surface of the core droplets is charged due to the absorption of SDS anionic, the Gelatin and Gum Arabic (GA) coacervating layer is easy to form there. The size of the GA microcapsules prepared with 0.003 wt% SDS is approximately 65 microm. Finally; the responsive behaviour of the microcapsules to electric field is also investigated.

Capsules↗
PubMed2003

Coupling ultrafiltration with an activated carbon cloth for the treatment of highly coloured wastewaters: a techno-economic study.

This work investigates the coupling of a membrane technique, ultrafiltration, with a recent adsorbent, activated carbon cloth for the treatment of industrial highly coloured wastewaters. A first experimental part shows the high treatment ability of this process for fountain-pen inks effluents arising from the rinsing of vats in which inks were produced. Whereas ultrafiltration enables more than 97% of colour removal, COD and DOC are not completely retained and a residual value of 1,700 mg l(-1) of DOC is obtained in the permeate. The second step of the process, activated carbon cloth, allows residual organic matter to be removed and a complete discolouring of the permeate. Adsorption capacities of COD and DOC are high, equal to 500 and 250 mg g(-1) respectively. Furthermore, this adsorbent induces a complete removal of glycol compounds (acting as antifreeze) which were not retined by a nanofiltration technique. A second part is an evaluation of the economic feasibility of such an integrated process. Only direct costs are considered at this phase of the study, and are divided into fixed costs (equipment, depreciation, maintenance), variable costs (electricity and consumption) and labour costs. The technical-economic study is carried out for two configurations: a low capacity unit (the UF membrane area is 2.4 m2) and an industrial capacity unit (with a 100 m2 UF membrane). Costs per treated m3 are respectively 111 and 32 euros, with costs partitioning which are dependent on the unit capacity.

Absorption↗
PubMed2001

Characterization of publication rotogravure press emission rates and compositions.

Emission compositions and rates were determined during production for a publication rotogravure press room at a large rotogravure printing company. The press room housed a single 4-color, 8-print-stand press, with an 84" paper web. Average press speed was 1800 feet per minute. Data were collected over a 2-day period and included measurements of ventilation, room area concentrations, duct exhaust compositions, amount and composition of inks used, and worker exposures. These data were used with mass balance models that were appropriate for the workspace. Toluene comprised more than 90 percent of the inks and solvents and accounted for more than 90 percent of the press emissions. Average toluene emissions during press operation and press off conditions were 222 kg/hr and 8-38 kg/hr, respectively. The uncontrolled toluene emission on the basis of printed paper throughput was 3 g/m2. Of the total toluene released, 90 percent was captured by the local exhaust ventilation. The measured control efficiency was much lower than the average efficiency of 97 percent for the month of the test reported by the plant. A mass balance model evaluation demonstrated that only the lower efficiency was consistent with measured room concentrations. Using the measured emission rates and actual monthly press on and press off conditions, the difference in efficiency for the plant (10 rotogravure presses) extrapolates to the additional release to the workspace and ambient environment of over 700 tons/yr of toluene.

Air Pollution, Indoor↗