Variation in zinc release from surface coatings as a function of methodology.

Over the last decade the growth of "nano-enabled" products have exploded in both industrial and direct to consumer applications. One area of interest is surface coatings, including paints, stains and sealants. Large scale applications of the products raise questions about both short- and long-term effects to both human and environmental health. Release of nanoparticles (NPs) from surfaces as a function of dermal contact is recognized as a potential human exposure route. Several standardized methods to quantify nanomaterial release have been previously used. In the current study, two standardized method were used to quantify the total mass of NPs released during sampling. ZnO (NPs) were used as a case study as they are commonly added to surface coatings to increase UV resistance. Particles were dispersed in Milli-Q water or a deck stain and applied to sanded plywood surfaces. Total release of Zn due to simulated dermal contact was evaluated using the Consumer Product Safety Commission (CPSC) and National Institute for Occupational Safety and Health (NIOSH) wipe methods. Additionally, three different sampling materials were tested. The total quantity of Zn released between the two methods was dependent upon the material used and how the ZnO was applied to the surface. Critically, less than 3% of the ZnO NPs applied to test surfaces was removed using either method. The results of this study demonstrate how different testing methodologies may result in varying estimates of human and environmental risk from NPs in surface coatings.

Release and transformation of nanoparticle additives from surface coatings on pristine & weathered pressure treated lumber.

As the market for "nano-enabled" products (NEPs) continues to expand in commercial and industrial applications, there is a critical need to understand conditions that promote release of nanomaterials and their degradation products from NEPs. Moreover, these studies must aim to quantify both the abundance and form (aggregates, ions, hybrids, etc.) of material released from NEPs to produce reasonable estimates of human and environmental exposure. In this work ZnO nanoparticles (NPs), a common additive in NEP surface coatings, were dispersed in Milli-Q water and a commercially available wood stain before application to pristine and weathered (outdoor 1 year) micronized copper azole pressure treated lumber (MCA). Coated lumber surfaces were sampled consecutively eight times using a method developed by the Consumer Product Safety Commission (CPSC) to track potential human exposure to ZnO NPs and byproducts through simulated dermal contact. Surprisingly, the highest total release of Zn was observed from aged lumber coated with ZnO NPs dispersed in wood stain, releasing 233 ± 26 mg Zn/m2 over the course of all sampling events. Alternatively, separate leaching experiments using a synthetic precipitation solution to simulate environmental release found aged lumber released significantly less Zn than pristine lumber when using the same coating formulation. Zinc speciation analysis also demonstrates that transformation of crystalline ZnO to Zn-organic complexes shortly after application to aged lumber. Regardless of experimental treatment, the majority of applied zinc (>75%) remains on the MCA surface. Finally, this work highlights how the nature of the screening technique (dermal contact vs. leaching) may result in different interpretations of exposure and risk.

Comprehensive management of hot-press hand injuries: long-term outcomes following reconstruction and rehabilitation.

Hot-press hand injuries create significant challenges, in terms of acute coverage and restoration of function, and long-term outcomes are largely unknown. This article reviews the comprehensive management of hot-press hand injuries--which includes damage control procedures, resurfacing, reconstruction, and rehabilitation--and assesses outcomes such as return to work and final impairment ratings. We treated 56 patients with hot-press hand injuries, at a verified, accredited burn center in the Southeast between 1994 and 2008. Mechanism included laundry press (42 cases), industrial press (11 cases), and home appliance (3 cases). Mean burn size was 118 cm2, with 43 full-thickness and 13 partial thickness injuries. Mean follow-up was 17.7 months. During this 15-year period, 39 patients (70%) were admitted acutely (mean length of stay: 10.4 days), 48 patients (86%) required operative intervention, and 28 patients (50%) had secondary reconstruction, which included nerve decompression (11 cases), contracture release (11 cases), tendon procedures (11 cases), and joint repair (5 cases). Mean final impairment rating was 22%, with 38 patients (68%) returning to work. Hot-press hand burns can be devastating, but return to work is possible for most patients. We recommend early wound excision, aggressive perioperative hand therapy, low threshold for reconstructive procedures, and rehabilitative support.

STARplasty for reconstruction of the burned web space: introduction of an alternative technique for the correction of dorsal neosyndactyly.

INTRODUCTION: Significant hand burns frequently result in dorsal neosyndactyly, despite appropriate wound care, excision/grafting, and occupational therapy. Patients often develop limited abduction, tethered flexion/extension, intrinsic tightness, and inversion of the web space. We present a new technique for neosyndactyly release: the STARplasty (Syndactyly Treatment After Release), named after the appearance of the reconstructed web. METHODS: We performed a retrospective review of 25 patients who underwent 66 web space reconstructions by a single surgeon, from January 2002 to December 2003. The STARplasty was developed prior to the study period, with the following goals: to use local tissue, negate the need for a skin graft, and permit early range of motion. Combined with longitudinal, transverse, and oblique releases, STARplasty uses a single volar flap, harvested from each sidewall of both proximal phalanges, with 30-degree corners. STARplasty simultaneously deepens and widens the web space while correcting the angle of inclination. RESULTS: Sixteen patients (mean age: 34 years; range: 3-62 years) underwent a total of 33 STARplasties, an average of 37 months after burn injury. Mean area resurfaced per web was 5.2 cm, which contrasts with the 33 non-STARplasty reconstructions, which were used to resurface a mean area of 19.4 cm (P < 0.05) and included 5-flap z-plasties (17), full-thickness skin graft (10), 2-flap z-plasties (3), and advancement flaps (3). No complications occurred in the STARplasty group, including infection, flap loss, dehiscence, nerve injury, or recurrent contracture. All patients had improved function (mean follow-up: 6.7 months; range: 1-18 months). CONCLUSIONS: STARplasty is a new, safe, and efficacious technique to correct dorsal neosyndactyly and reconstruct the web space after burn injury.