Uma opção seria
library(scatterplot3d)
x=c(-1,-1,-1,-1,-1,0,1,0,0,1,0,0,1,1,0)
y=c(-1,-1,0,1,0,1,0,-1,-1,-1,-1,1,1,0,0)
z=c(-1,0,1,0,-1,-1,-1,-1,1,0,-1,1,0,1,0)
w=scatterplot3d(x,y,z, highlight.3d = T, angle = 45,
scale.y = .5,xlab="Concentração", ylab="pH",
zlab="Agitação",col.axis="blue",type="n")
w$points3d(x,y,z,col="red",pch=20,cex=5)
# calcula media e desvio por ponto
med <- format(apply(cbind(x, y, z), 1, mean), digits = 3)
dp <- format(apply(cbind(x, y, z), 1, sd), digits = 3)
dp <- paste("(", dp, ")", sep = "")
# cria o label
lab <- paste(med, dp, sep = "\n")
# insere o label
text(w$xyz.convert(x, y, z), labels = lab, pos = 4, cex = .7)